Molecules {hydrocarbon}| can have only carbon and hydrogen.
Carbon atoms in sequences or rings can attach hydrocarbon chains or rings {side chain, hydrocarbon} {hydrocarbon side chain}.
Carbon atoms in sequences or rings can attach atoms or atom groups {substituent group}|.
Carbon atoms {carbon}| can attach carbons to make sequences or rings.
non-metals
Carbon forms covalent bonds with non-metals. Carbon and chlorine make the volatile liquids carbon tetrachloride and chloroform. Carbon and fluorine make the liquid refrigerant Freon and the solid fluorocarbon Teflon. Carbon and oxygen make carbon monoxide gas and carbon dioxide gas. Carbon and nitrogen make cyanide ion with triple bond between nitrogen and carbon, nitrile compounds with triple bond between nitrogen and carbon, imine compounds with double bond between nitrogen and carbon, and amine compounds with single bond between nitrogen and carbon.
Carbon atoms {primary carbon} can attach to only one other carbon atom.
Carbon atoms {secondary carbon} can attach to two other carbon atoms.
Carbon atoms {tertiary carbon} can attach to three other carbon atoms.
Carbon atoms {carbanion} can gain unshared electron pairs and have only three bonds, to become electrophiles. Carbanions can be in organic bases.
Carbon atoms {carbocation} {carbonium ion} can lose electron pairs and have only three bonds, to become nucleophiles. Carbocations are more in polar solvents. Carbocations are more at tertiary carbons than at secondary or primary carbons.
Aliphatic hydrocarbons can be chains {alkane}| or rings {cycloalkane}. Small alkanes have one carbon {methane}, two carbons {ethane}, three carbons {propane}, four carbons {butane}, five carbons {pentane}, six carbons {hexane}, seven carbons {heptane}, or eight carbons {octane}.
branching
Alkanes {n-alkane} can have no branches. Alkanes {iso-alkane} can branch at second carbon. Alkanes {neo-alkane} can have two single-carbon side-chain methyl groups on second carbon. Alkanes can have functional group on second carbon {sec-}. Alkanes can have functional group and carbon side chain on second carbon {tert-}.
properties
Alkanes are colorless, odorless, not polar, not reactive, not acidic, not basic, and oxidizable. If alkane has one to four carbons, it is gas. If alkane has five to nineteen carbons, it is liquid. If alkane has more than nineteen carbons, it is waxy solid.
Hydrocarbons {aliphatic}| can have only single bonds.
Alkanes {alkyl group} can attach to carbon chains as side chains.
Alkanes can have single-carbon side chains {methyl group}.
Mixtures {naphtha} can have alkanes with four to ten carbons.
Mixtures {kerosene} can have alkanes with nine to fifteen carbons.
Mixtures {diesel fuel} can have alkanes with fifteen to twenty-five carbons.
Mixtures {lubricating oil} can have alkanes with more than 20 carbons.
Mixtures {asphalt} can have alkanes with more than 30 carbons.
Hydrocarbons {alkene}| {olefin} can have at least one double bond. Small alkenes have two carbons {ethylene} {ethene} or three carbons {propylene} {propene}. Alkenes are colorless, odorless, reactive, not polar, not acidic, not basic, and oxidizable or reducible. Alkenes with two to four carbons are gases. Alkenes with more than four carbons are liquids.
Alkanes can attach halides {alkyl halide}. Alkyl halides are colorful, smell powerful and bad, are very reactive, are polar, are not acidic or basic, and are not oxidizable or reducible. Alkyl halides are liquids, except for methyl halide gases. Alkyl halides are heavier than water.
Alkene substituents {allyl} can have three carbons and double bond at far end from carbon chain.
Ethylenes {vinyl group} can be side chains.
Hydrocarbons {alkyne}| can have at least one triple bond. The smallest alkyne has two carbons {acetylene} {ethyne}. Alkynes are colorless, odorless, reactive, not polar, not acidic, not basic, and oxidizable or reducible. Alkynes are gases.
C2H2 [2 is subscript] {carbene} is like methylene and has singlet or triplet spin states.
Hydrocarbons {aromatic compound}| {aryl compound} can have planar ring of six carbons, five carbons and one nitrogen or oxygen, or four carbons and one nitrogen or oxygen.
properties
Aromatics are colorless, have gasoline-like smell, are not polar, and are not acidic or basic. Rings are not oxidizable or reducible and are unreactive.
resonance
Ring has resonating single and double bonds, which delocalize electrons into two rings, one above and one below planar ring.
substituents
Hydroxyl, ether, ester, amine, alkyl, halide, and phenyl groups donate electrons to aromatic rings. Nitro, cyanide, carboxyl, aldehyde, ketone, sulfoxide, and hydrogen groups take electrons from aromatic rings, as do ammonium ion and primary amine ion.
ring number
Aromatic compounds can have three aromatic rings {anthracene}, four aromatic rings {tetracene}, five aromatic rings {pentacene}, and so on {polyacene} {acene}.
ring number: phase
Aromatic compounds with one ring are liquids. Aromatic compounds with more than one ring are solids.
examples
Explosive aryls include TNT and picric acid. Aryls include vanillin, toluidine, indole, cholesterol, and menthol.
Aromatic compounds {naphthalene} can have two aromatic rings.
Six-carbon aromatics {benzene} can have no side chains. Benzene can be functional group {phenyl-}. Compound can have methylbenzene functional group {benzyl-}. Benzene rings can have same side chains at opposite carbons {para-, benzene ring}, on adjacent carbons {ortho-, benzene ring}, or separated by one carbon {meta-, benzene ring}.
Benzene rings {anisole} can have methyl ether side chain.
Benzene rings {cresol} can have hydroxyl side chain and adjacent methyl side chain.
Benzene rings {cumene} can have isopropyl side chain.
Benzene rings {aniline} can have amine side chain, as in dyes, indicators, and pigments. Aniline can have positive ion {anilinium}.
Benzene rings {phenol} can have hydroxyl side group, as in dyes, indicators, and detergents {alkylphenol}.
Benzene rings {styrene} can have ethene side chain.
Benzene rings {thymol} can have hydroxyl side group, adjacent isopropyl side chain, and opposite methyl side chain.
Benzene rings {toluene} can have methyl side chain.
Benzene rings {xylene} can have two methyl side chains.
Organic compounds {alcohol, chemical}| can have carbon atom single-bonded to hydroxyl group: -C-O-H. Alcohols are colorless, have pungent and sweet odor, are reactive, are polar, are basic or acidic, and are oxidizable and reducible. Alcohols with less than twenty carbons are liquids. Alcohols dissolve in water if they have less than six carbons. Carbon atom with two hydroxyl side chains is unstable and reverts to aldehyde or ketone.
Organic compounds can have carbon atom single-bonded to oxygen atom single-bonded to hydrogen atom {hydroxyl group}: -O-H.
Sodium or magnesium metal can remove hydrogen atom from alcohol oxygen atom to make hydrogen gas and ion {alkoxide ion} with charge -1: -C-O- [last - is superscript].
Sulfuric or hydrobromic acid can add hydrogen atom to alcohol oxygen atom to make unstable ion {alkyloxonium ion} {oxonium ion} with charge +1: -C-O+H2 [+ is superscript, and 2 is subscript].
Alcohols {ethylene glycol} can have two carbons, each with one hydroxyl group.
Alcohols {glycerol, alcohol} can have three carbons, each with one hydroxyl group.
Organic compounds {amine, organic}| can have carbon atom single-bonded to nitrogen atom: -C-N-. Amines are colorful, have pungent powerful odor, are slightly reactive, are polar, and are not oxidizable or reducible. Amines are liquids, except for ammonia gas. Amines are slightly basic if they have zero or one alkyl group, highly basic if they have two or three alkyl groups, and even more highly basic if alkyl group has double bond.
Amines {azide}| can have only three nitrogens.
A nitrogen atom can single-bond to a carbon atom and double-bond to a nitrogen atom, with only hydrogens on other bonds, in resonating structures {diazonium ion}.
A carbon atom can bind to three nitrogens, including one double bond, with only hydrogens bonded to nitrogens, in resonating structures {guanidium ion}.
Amines {piperidine} can have one non-aromatic ring with five carbons and one nitrogen atom.
Amines {pyrrolidine} can have one non-aromatic ring with four carbons and one nitrogen atom.
One carbon atom can double-bond to one nitrogen atom single-bonded to another carbon atom {Schiff base}: C=N-C.
Ketones and aldehydes have carbon atom double-bonded to oxygen atom {carbonyl}. Aldehydes and ketones are colorless, have sweet odor, are polar, are not acidic or basic, are oxidizable to carboxylic acids, and are reducible to alcohols. Carbonyls are reactive. Aldehydes are more reactive than ketones. Aldehydes and ketones are liquids unless they have more than twenty carbons. Small aldehydes and ketones dissolve in water.
Aldehydes and ketones can be substituents {oxy-}.
In aldehyde or ketone carbonyl groups, carbon has slight positive charge and oxygen has slight negative charge. Aldehyde or ketone can hybridize to have positive carbon atom and negative oxygen atom {enolate ion}, with single bond between carbon and oxygen.
If aldehyde or ketone carbonyl carbon attaches to another carbon, the double bond can move between the carbons, and hydrogen atom from second carbon can move to oxygen {keto-enol isomerism}.
Carbonyl can be at carbon-chain end {aldehyde}|: -C=O.
The smallest aldehyde {methanal} {formaldehyde, carbonyl} has one carbon atom.
Aldehydes {ethanal} {acetylaldehyde} can have two carbon atoms.
Other aldehydes {benzaldehyde} or ketones are in camphor, citral, vanillin, cinnamon, and almonds.
Carbonyl can be in carbon-chain middle {ketone}|: =C=O.
The smallest ketone {propanone} {methyl methyl ketone} {acetone} has three carbons.
Ketones {lactone} can have rings with five carbon atoms and one oxygen atom. One carbon atom double-bonds to an oxygen atom outside ring.
Organic compounds {carboxylic acid}| can have terminal carbon atom double-bonded to oxygen atom and single-bonded to hydroxyl group.
properties
Carboxylic acids are colorless, have strong and bad odor, are reactive, are polar, are acidic, and are reducible to aldehydes. Carboxylic acids are liquids if they have less than twelve carbons.
types
Small carboxylic acids have one carbon {methanoic acid} {formic acid}, two carbons {ethanoic acid} {acetic acid}, three carbons {propanoic acid} {propionic acid}, four carbons {butanoic acid} {butyric acid}, five carbons {pentanoic acid} {valeric acid}, or six carbons {hexanoic acid} {caproic acid}.
types: saturated fatty acids
Larger carboxylic acids have twelve carbons {lauric acid}, fourteen carbons {myristic acid}, sixteen carbons {palmitic acid}, eighteen carbons {stearic acid}, or twenty carbons {arachidic acid}.
types: unsaturated fatty acids
Fatty acids can have double bonds in carbon chain. First double bond is at ninth carbon, second is at twelfth carbon, and third is at fifteenth carbon. Sixteen carbons can have one double bond {palmitoleic acid}. Eighteen carbons can have one double bond {oleic acid}. Eighteen carbons can have two double bonds {linoleic acid}. Eighteen carbons can have three double bonds {linolenic acid}. More double bonds increase fatty-acid liquidity.
derivatives
Carboxylic-acid derivatives substitute nucleophile for carboxylic-acid hydroxyl group. Nucleophile can be ether to make ester, amine to make amide, carboxylic acid to make anhydride, or halide to make acyl halide.
Carboxylic acids can be substituents {acyl-}.
Carboxylic acids dissolve in water and lose proton to make ion {carboxyl ion}. Carboxyl ion has resonance between single and double bonds to oxygens.
Carboxylic acids have salt forms {carboxylate}, which use suffix -ate, as in sodium citrate.
Long fatty acids can add sodium ion to make sodium salt {soap}|.
Carboxylic acids {carbonic acid} can have one carbon, three oxygens, and two hydrogens.
Carboxylic acids {dicarboxylic acid} can have carboxyl groups on both ends. Small dicarboxylic acids have two carbons {oxalic acid}, three carbons {malonic acid}, four carbons {succinic acid}, five carbons {glutaric acid}, or six carbons {adipic acid}.
Propanoic acid {lactic acid} can have hydroxyl group on second carbon.
Organic molecules {limonene} can be skin irritants.
Benzene rings {phthalic acid} can have adjacent carboxyl group. Phthalates can affect body hormone levels.
Propanoic acid {pyruvic acid} can have ketone on second carbon.
Benzoic acid {salicylic acid} can have a hydroxyl group in para- position.
large dicarboxylic acid {tartaric acid} {cream of tartar, acid}.
Branched carbon chain can have three carboxyl groups {tricarboxylic acid}, such as citric acid.
Carboxylic-acid nucleophile can substitute for carboxylic-acid hydroxyl group. Organic compounds {acid anhydride} can have last carbon in carbon chain double-bonded to oxygen atom and single-bonded to carboxylic acid. Acid anhydrides are colorless, smell bad like carboxylic acids, are highly reactive, are polar, are not acidic, are not basic, are not oxidizable or reducible, dissolve slightly in water, and are liquids unless more than six carbons.
Acid anhydrides {imide}| can be amides.
Organic compounds {acyl halide} can have last carbon in carbon chain double-bonded to oxygen atom and single-bonded to halogen. Acyl halides are colorful, have harsh and pungent and bad odor, are highly reactive, are polar, are not acidic, are not basic, are not oxidizable or reducible, dissolve slightly in water, and are liquids unless more than six carbons.
Organic compounds {amide}| can have last carbon in carbon chain double-bonded to oxygen atom and single-bonded to amino group. Amides include urea, phenobarbitol, and caffeine.
properties
Amides are colorful, have harsh and pungent and bad odor, are slightly reactive, are polar, are not acidic, are not basic, are not oxidizable or reducible, dissolve slightly in water, and are liquids unless more than six carbons.
bond
Amide bonds resonate, because double bond between carbon and oxygen can shift to nitrogen, making nitrogen positive, carbon positive, oxygen negative, and bond planar.
Nitrogen makes organic compounds {nitrogen compounds}. Organic compounds {nitro organic compounds} can have nitrogen atom double-bonded to oxygen atom and single-bonded to another oxygen atom: -O-N=O.
Nitrogen compounds {cyanide} can have carbon atom triple-bonded to nitrogen atom and single-bonded to hydrogen atom.
Nitrogen compounds {hydrazine} can have two nitrogens and six hydrogens, with double bonds.
Nitrogen aromatic compounds {imidazole} can have three carbons and two nitrogens, separated by carbon atom, in ring.
Nitrogen compounds {imine}| can have nitrogen-carbon double bond.
Nitrogen compounds {nitrile}| can have carbon atom double-bonded to nitrogen atom, -C=N-. Nitrile side chains {isonitrile} have carbon on end and nitrogen double-bonded to another carbon: C-N=C-. Isonitriles usually smell strong and bad.
One nitrogen atom can double-bond to two oxygen atoms, so nitrogen has positive charge {nitronium ion}: O=N+=O.
One carbon atom can double-bond to one nitrogen atom single-bonded to hydroxyl {oxime}: -C=N-OH.
Nitrogen aromatic compounds {pyridine} can have five carbon atoms and one nitrogen atom in ring.
Nitrogen aromatic compounds {pyrimidine, nitrogen} can have four carbons and two nitrogens, separated by carbon atom, in ring.
Nitrogen aromatic compounds {pyrrole} can have four carbon atoms and one nitrogen atom in ring.
Organic compounds {ester}| can have carbon-chain last carbon double-bonded to oxygen atom and single-bonded to alkoxyl group.
properties
Esters are colorless, smell good and sweet, are reactive, are polar, are not acidic, are not basic, are not oxidizable or reducible, and dissolve somewhat in water. Esters are liquid unless more than six carbons.
derivatives
A phosphate group {phosphate ester} can replace carboxylic-acid hydroxyl group. A sulfate group {sulfate ester} can replace carboxylic-acid hydroxyl group. Alkylbenzene-sulfonic-acid sodium salt detergent is sulfate ester. A sulfhydryl group {thioester} can replace carboxylic-acid hydroxyl group. Thioesters are more reactive than esters. Thioesters can ionize as thiolate ion to make weak base.
Carbon atom at carbon-chain end can have hydroxyl group and ether side chain {hemiacetal}. Carbon atom at carbon-chain end can have two ether side chains {acetal}.
Carbon atom in carbon-chain middle can have hydroxyl group and ether side chain {hemiketal}. Carbon atom in carbon-chain middle can have two ether side chains {ketal}.
Oxygen atom single-bonded to carbon atom {alkoxyl group}, -O-C, can attach to carbon atom.
Organic compounds {epoxy} {oxirane} can have a ring with two carbons and one oxygen.
Organic compounds {ether, chemical}| can have an oxygen atom single-bonded between two carbons: -C-O-C-. Ethers are colorless, have pungent and sweet odor, are slightly reactive, are non-polar, are not basic or acidic, and are oxidizable or reducible. Ethers can dissolve in water if small. Polybrominated diphenyl ethers are flame-retardant chemicals.
Ether rings {dioxane} can have four carbons and two opposite-side oxygens, with no double bonds. Dioxane can dissolve in water.
Ether rings {oxazole} can have, oxygen, carbon, nitrogen, and two carbons.
Phenol can have carbon atom single-bonded to benzene {R group}, which is single-bonded to hydroxyl {phenyl}, -R-CH2-O-H [2 is subscript].
Aromatic compounds {furan} can have four carbon atoms and one oxygen atom in ring. Tetrahydrofuran can dissolve in water.
Aromatic compounds {pyran} can have five carbon atoms and one oxygen atom in ring.
Organic compounds {sulfur organic compound} can have carbon atom single-bonded to sulfur. Perhaps, mercaptan vials or rings can open if people are in danger. Bad smells repulse attackers. Splashing some on attackers is a mark hard to remove.
Organic compounds {sulfide} can have sulfur bonded between two carbons, -C-S-C-.
Two thiols can react to eliminate hydrogens from sulfurs and make sulfur-sulfur bond {disulfide bond}.
Three carbons can bond to one sulfur to give sulfur positive charge {sulfonium ion}.
Compounds {thioether} similar to ethers have sulfur atom instead of oxygen atom.
Sulfhydryl groups can replace carboxylic-acid hydroxyl groups to make thioesters. Thioesters are more reactive than esters. Thioesters can ionize {thiolate ion} to make weak bases.
Alkylbenzene-sulfonic-acid sodium salt is sulfate ester {detergent}|.
Organic compounds can have carbon atom single-bonded to sulfur atom, which is single-bonded to hydrogen atom {sulfhydryl group}, -S-H.
Sulfhydryls {thiol} {mercaptan} are similar to alcohols, but sulfur replaces oxygen. Hydrogen sulfide has rotten-egg smell. Beta-mercaptoethanol has bad smell. Thiols can be side chains. Thiols are colorless, have bad odor, are reactive, can be more acidic than alcohols or can be basic, and are oxidizable and reducible.
Molecules {polymer}| can link repeated subunits into sequence. Carbohydrates, proteins, and nucleic acids are polymers.
mass
Polymers have masses of 10,000 to 100,000 dalton. Masses have normal distribution, skewed toward lower masses. Centrifugation or light scattering can indicate mass.
osmotic pressure
Polymer osmotic pressure is higher than ideal solution pressure, because polymers are large molecules.
colloid
Polymers make colloids, because molecules are long.
viscosity
Polymer viscosity depends on molecule size and shape. Shape has four parameters: moments in three spatial dimensions and orientation.
Polymers {plastic, chemistry}| can have hydrocarbon subunits. Thermoplastics melt if heated. Thermosetting plastics do not melt if heated. Plastics can have covalent or hydrogen bonds that cross-link polymer chains.
types
Nitrocellulose was first plastic [1879] and comes from cellulose. It was in the first billiard balls and then in dental plates and Celluloid shirt collars. Nitrocellulose is in combs, brushes, eyeglass frames, film negatives, and car lacquer.
Cellulose acetate was second plastic invented, comes from cellulose, coats fabric-covered airplanes, is in model airplane glue, and is in nail polish, mixed with acetone.
Polyethylene comes from ethylene.
Polystyrene comes from styrene.
Polyvinyl chloride or PVC comes from vinyl chloride.
Acrylic comes from acrylonitrile.
Polyester comes from ethylene glycol and propylene glycol.
Nylon comes from amide.
Polymers {elastomer} can stretch and then resume shape, because normally they are contracted chains. Elastic polymers have cis double bonds, to allow stretching.
Nitrocellulose {cellophane} can be for wrapping.
Nitrocellulose {rayon} can be fibers.
Rayon and cellophane have basic units {viscose}.
Organic molecules have carbon chemical reactions {chemical reaction, organic}.
Organic molecules can have acid-base reactions {acid-base reaction, organic}.
acidity
Bonds from highest to lowest acidity are H-Br, H-Cl, H-F, H-S-, H-O-, H-N-, and H-C-. From highest to lowest acidity, compounds are inorganic acids, carboxylic acids, alkylammonium ion, thiol, phenol, and alcohol.
basicity
From highest to lowest basicity, organic and inorganic compounds are -NH2- [2 is subscript and last - is superscript] or nitride, -R-O- [last - is superscript] or alkoxide, -O-H, -S-H, -Cl, NH3 [3 is subscript] or ammonia, and H2O [2 is subscript] or water.
neutral
Ketones, aldehydes, alkenes, and alkanes are neither acids nor bases.
Lewis
Lewis bases can attack double bond between carbons to make negatively charged carbanion. Lewis acids can attack double bond between carbons to make positively charged carbonium ion.
Organic reactions {addition reaction} can bind substituents to double bond to make two single bonds.
For double bond between two carbons, carbons have two other constituents. Molecule is planar, with constituent angles of 120 degrees. See Figure 1.
Electrophile, typically hydrogen ion, slowly attacks double-bond electrons to make carbocation. In addition reactions, hydrogen atom binds to primary carbon, by Markownikoff's rule. See Figure 2.
Then nucleophile quickly adds to the other tertiary or secondary carbon, which is more polar than primary carbon atoms. See Figure 3.
conformation
Conformation is typically cis, but is trans for two similar substituents.
polarity
Terminal carbon double bonds are not sufficiently polar for attack, but internal double bonds are polar enough for attack.
alkenes
Alkenes have double bonds between carbons. Alkene + water -> alcohol. Alkene + ammonia -> amine. Alkene + halogen acid -> alkyl halide. Alkene + hydrogen gas -> single bond. Alkene + halogen gas -> alkyl halide, on both carbons with trans conformation.
Oxidation-reduction reactions {Belousov-Zhabotinskii reaction} {Belosov-Zhabotinski reaction} (B-Z reaction) (BZ reaction) using sodium bromate, malonic acid, sulfuric acid, and cerium ions, and involving twenty-one reaction steps, can produce spatial patterns in dishes, after delays.
As shown by ferroin indicator, cerium-ion catalysts change oxidation state, blue and magenta, or do not change oxidation state, yellow and clear, to make concentric circles or spirals. Concentrations oscillate with period {limit cycle, concentration}.
feedback
Oscillation happens only far from chemical equilibrium and requires feedback.
diffusion
Spatial patterns require diffusion.
chemical patterns
Non-linear multiple-reaction kinetics and feedback, through diffusion or direct chemical addition, can form temporal and spatial patterns far from equilibrium. Patterns require flows and feedback. Reaction far from equilibrium between high-concentration species typically affects low-concentration catalytic compound, which can have two different oxidation states or shift easily between acid and base. Reaction rates oscillate.
Chemical-pattern formation depends on dissipative structure theory. Turing [1952: The Chemical Basis of Morphogenesis] invented chemical and biological spatial-pattern-formation theory. Belousov and Zhabotinskii [1958, 1964] discovered oscillating chemical reaction, and Noyes [1972] analyzed mechanism {oregonator model}.
Continuous-flow stirred-tank reactor (CSTR) studies oscillating systems over time. Continuous-flow unstirred reactor (CFUR) studies oscillating systems over space.
Substitution into benzene rings {benzene ring reaction} replaces a hydrogen on a ring carbon with nitro, sulfoxy, halogen, or other nucleophilic substituent.
process
Strong acid, such as iron (III) chloride or aluminum chloride, can slowly polarize benzene-ring carbon atom to make carbocation. Carbocation resonates at attacked-carbon ortho carbon and para carbon. Nucleophile quickly adds to attacked carbon, and hydrogen ion leaves.
process: already substituted
If benzene ring already has one nitro, sulfoxyl, halogen, or other nucleophilic substituent, substituted nucleophile substituent has positive charge.
If benzene ring already has one nitro, sulfoxyl, halogen, or other nucleophilic substituent, electron-donating nucleophilic substituent quickly adds to substituted-carbon ortho carbon or para carbon.
If benzene ring already has one nitro, sulfoxyl, halogen, or other nucleophilic substituent, and bromine or strong acid polarizes carbon atom to make carbocation, electron-withdrawing nucleophile can slowly add to substituted-carbon meta carbon.
resonances
Meta carbon and substituted carbon have three resonance structures. Substituted carbon and ortho or para carbons have four resonance structures.
Carboxylic acid and ester can combine to make longer carbon chain {carbon chain reaction}, if negatively charged nucleophile is present. Negatively charged nucleophile can create carbanion on carboxylic-acid second carbon. Carbanion can attack ester. Negative charge migrates to ester double-bonded oxygen. First ester carbon bonds to first carboxyl carbon. Carboxyl reforms as nucleophile leaves, leaving new carbon-carbon single bond.
To add carbon atom to carbon chain {condensation reaction, organic}, aldehyde or ester combines with alcohol, to make new carbon-carbon single bond and water molecule.
Cyanide and alkyl chloride can react to lengthen alkyl carbon chain by adding cyanide carbon {cyanide reaction}. Reaction releases nitrogen and chloride.
Organic reactions {electrophilic addition reaction} can add electrophilic substituent to carbonyl group.
carbonyl
Carbonyl groups have double bond between carbon and oxygen. Carbonyl groups are planar, with two substituents on carbon and none on oxygen. Bond angles are 120 degrees. See Figure 1.
process
Hydrogen ion attacks carbonyl oxygen and adds to it, making positive charge. Double bond does not break. See Figure 2.
Then positive charge migrates to carbonyl carbon to make carbocation. See Figure 3.
Then water or alcohol adds to carbon. See Figure 4. Hydrogen at carbonyl oxygen and hydrogen at nucleophile leave and combine to make hydrogen gas.
In alcohols, amines, or alkyl halides, organic reactions {elimination reaction} can make two substituents leave adjacent carbon atoms and form double bond. Acid or base starts reaction.
acid and alcohol
For example, compound can be alcohol. See Figure 1.
Acid pulls off nucleophile, and hydrogen atom leaves. See Figure 2. Double bond forms, and then acid reforms. See Figure 3.
base and alcohol
For example, compound can be alcohol. See Figure 4. Base pulls hydrogen atom from carbon with no substituent. See Figure 5. Nucleophile leaves other carbon. Double bond forms, and base reforms. See Figure 6.
E1 elimination
Secondary or tertiary carbon carbocation can form slowly, and then double bond forms quickly {E1 elimination}. Secondary or tertiary carbon is more polar than primary carbon. Acid or base starts this elimination type.
E2 elimination
Molecule can slowly push substituent from primary carbon, because primary carbons have no large substituents and low polarization. Bond breaks, and double bond quickly forms {E2 elimination}. See Figure 7, Figure 8, and Figure 9.
base
If strong base is present and reactant is alcohol or alkyl halide, mechanism favors eliminations over substitutions, because base can strongly attract hydrogen atom. If reactant is amine or carboxylic-acid derivative and nucleophile is neutral or acidic, substitution happens more than elimination.
Free radical can attack double bond between carbons {free radical reaction}, to make neutral atom with odd-numbered electron configuration at carbon atom.
Aryl or alkyl group single-bonded to magnesium halide can react with carbonyl-group carbon to lengthen aryl-group or alkyl-group carbon chain by adding carbonyl-group carbon atom {Grignard reagent reaction}.
In addition reactions, hydrogen atom binds to primary carbon {Markownikoff's rule} {Markownikoff rule}.
Organic reactions {nucleophilic addition reaction} can add nucleophilic substituent to carbonyl group.
nucleophilic attack
Water molecule, alcohol, hydride ion, carbide ion, ammonia molecule, or amine nucleophile can attack carbonyl carbon.
carbonyl
Carbonyl groups have double bond between carbon and oxygen. Carbonyl groups are planar, with two substituents on carbon and none on oxygen. Bond angles are 120 degrees. See Figure 1.
hydrogen
Water molecule, alcohol, or hydride ion attacks carbonyl carbon to make tetrahedral carbocation. Carbocation and negatively charged oxygen resonate with double-bonded carbon and oxygen. See Figure 2. If carbonyl carbon is not single-bonded to carbon atom, carbonyl oxygen adds hydrogen atom. See Figure 3. If carbonyl carbon is single-bonded to carbon atom, hydrogen from second carbon can migrate to oxygen to make alcohol and carbanion, or stay at second carbon to make carbocation and oxygen ion, by tautomerism. See Figure 4.
carbide
Carbide ion attacks carbonyl carbon. See Figure 5. Carbide negative charge migrates to oxygen. See Figure 6. Double bond forms between carbonyl carbon and carbide carbon. See Figure 7. Positively charged hydrogen ion from acid adds to negatively charged oxygen to make hydroxyl and one bond between carbons. See Figure 8. Carbide reacts with carbonyl to make new carbon-carbon single bond at tetrahedral carbon {condensation reaction, nucleophilic}.
nitrogen
Ammonia or amine attacks carbon. See Figure 9, Figure 10, Figure 11, and Figure 12. Double bond forms between carbonyl carbon and amine nitrogen atom. Oxygen leaves with two hydrogens, to make water. See Figure 13.
After initiation, molecule {plasticizer} can better link polymer subunits by covalent bonds.
Carbon chains can extend {polymerization}| by attaching a subunit to chain end and then repeating. Organisms use energy, inorganic nutrients, and organic nutrients to make molecules {precursor, biology} that polymerize to make biological polymers.
reactions
Polymers can form using addition reactions with acids, bases, radicals, or ions. Polymers can form using condensation reactions, in which water molecule leaves as bond forms between carbon atom and carbon or oxygen atom.
process
Polymerization has three steps.
Sulfuric acid, strong inorganic or organic base, or organic-peroxide radical makes carbocation, carbanion, or free radical, respectively, in subunit and then double bond breaks {initiation, polymerization}.
Carbocation, carbanion, or free radical, respectively, attacks other-subunit double bond, in addition reactions, to make one bond from first carbon to first subunit carbon. Plasticizer molecule helps covalently bond subunits.
Added base terminates acid reaction, added acid terminates base reaction, or two free radicals react to make terminal bond {termination}.
Organic reactions {proton transfer reaction} can involve hydrogen-ion migration.
Organic compounds can oxidize or reduce {redox reaction, organic}. Organic compounds, from most to least oxidized, are carboxylic acid, ketone and aldehyde, alcohol, alkene, and alkane. Organic compounds can oxidize to higher oxidation with potassium chromate, potassium permanganate, ozone, or oxygen. Organic compounds can reduce to lower oxidation with sodium metal, magnesium metal, zinc metal, sodium thiosulfate, acids, and hydrogen gas. If no water is present, lithium aluminum hydride or sodium borohydride can reduce aldehydes and ketones to alkoxides.
Organic reactions {substitution reaction, organic} can substitute nucleophiles. In reactant, two carbons share one bond, and secondary or tertiary carbon has small and weak nucleophile. See Figure 1.
substitution type 1
Bigger and stronger nucleophile can substitute for weaker and smaller nucleophile, at rate that depends on reactant concentration {substitution type 1} (SN1).
In slow step, polar solvent separates substituent from molecule, making secondary or tertiary carbocation. Secondary or tertiary carbons have more polarity, have larger substituents, and prevent pushing more, compared to primary carbons. See Figure 2.
In fast step, other substituent substitutes for separated substituent, helped by polar solvent. See Figure 3. SN1 reactions are not stereospecific, because pull can be from any side.
For example, hydroxyl or cyanide substitutes for halide. Amine substitutes for hydroxyl.
substitution type 2
In reactant, two carbons share one bond, and primary carbon has large and strong nucleophile. See Figure 4.
Weak and small nucleophile can substitute for bigger and stronger nucleophile, with rate that depends on two reactant concentrations {substitution type 2} (SN2).
First, electric repulsions from second molecule push away substituent from first molecule, giving intermediate state. Intermediate state is planar, because five substituents attach to carbon. See Figure 5.
Old substituent leaves, helped by non-polar solvent. SN2 reactions have stereospecific product, because pushing can be from one side only. See Figure 6.
To make carboxylic-acid derivatives, nucleophile attaches to carboxyl carbon to make tetrahedral carbon {tetrahedral carbonyl addition compound}. Nucleophiles from strongest to least strong are hydroxyl, amine, alkoxyl, halide, and carboxyl. Acid catalyst can attack carboxyl double bond. Then old nucleophile leaves as carboxyl reforms.
Functional groups can attack tetrahedral carbon from one side {Walder inversion}. The new functional group pushes off opposite functional group and binds, causing tetrahedron inversion.
Ethers can form by substitution reaction {Williamson synthesis}.
Outline of Knowledge Database Home Page
Description of Outline of Knowledge Database
Date Modified: 2022.0225