BIO - TERMS - CARBON Flashcards
1,3-Diaxial interaction
The strain energy caused by a steric interaction between axial groups three carbon atoms apart in chair cyclohexane.
activated carbon
Very fine carbon particles with high surface area. (24.5) activated complex (transition state) A high-energy intermediate state between reactant and product.
Alkyl halide
A compound with a halogen atom bonded to a saturated, sp3-hybridized carbon atom.
Alkylation
Introduction of an alkyl group onto a molecule. For example, aromatic rings can be alkylated to yield arenes, and enolate anions can be alkylated to yield α-substituted carbonyl compounds.
Anti conformation
The geometric arrangement around a carbon–carbon single bond in which the two largest substituents are 180° apart as viewed in a Newman projection.
Anti periplanar
Describing the stereochemical relationship in which two bonds on adjacent carbons lie in the same plane at an angle of 180°.
aromatic hydrocarbon
Any hydrocarbon containing a stabilized planar ring of carbon atoms, most commonly a benzene ring.
asymmetric carbon atom
A carbon atom that is covalently bonded to four different groups and thus may exist in two different tetrahedral configurations.
Betaine
A neutral dipolar molecule with nonadjacent positive and negative charges. For example, the adduct of a Wittig reagent with a carbonyl compound is a betaine.
Branched-chain alkanes
Alkanes that contain a branching connection of carbons as opposed to straight-chain alkanes.
C4 carbon fixation
The biochemical pathway of CO2 fixation in C4 plants. It involves fixing of CO2 in mesophyll cells via phosphoenolpyruvate PEP, carboxylase formation of the eponymous C4 compound, usually malate, which is transported to the bundle-sheath cells where after its decarboxylation CO2 is fixed by Rubisco.
C4 plants
Plants (generally tropical) in which CO2 is first fixed into a four-carbon compound (oxaloacetate or malate) before entering the Calvin cycle via rubisco.
Cahn–Ingold–Prelog sequence rules
A series of rules for assigning relative rankings to substituent groups on a chirality center or a double-bond carbon atom.
Carbaminohemoglobin
Hemoglobin with carbon dioxide covalently bound to its terminal amino groups.
Carbene, R2C
A neutral substance that contains a divalent carbon atom having only six electrons in its outer shell (R2C:).
carbides
Binary compounds composed of carbon and a low-electronegativity element.
Carbinolamine
A molecule that contains the R2C(OH)NH2 functional group. Carbinolamines are produced as intermediates during the nucleophilic addition of amines to carbonyl compounds.
carbon black
A fine powdered form of carbon.
carbon cycle
The series of processes that converts CO2 to organic substances and back to CO2 in nature.
Carbon monoxide
A competitive inhibitor of oxygen binding to hemoglobin and myoglobin.
carbon-assimilation reactions
Reaction sequence in which atmospheric CO2 is converted into organic compounds.
Carbonyl condensation reactions
A type of reaction that joins two carbonyl compounds together by a combination of alpha-substitution and nucleophilic addition reactions.
chemical group
Certain combinations of atoms—such as methyl (–CH3), hydroxyl (–OH), carboxyl (–COOH), carbonyl (–C=O), phosphate (–PO3 2–), sulfhydryl (–SH), and amino (–NH2) groups—that have distinct chemical and physical properties and influence the behavior of the molecule in which the group occurs.
chemoautotroph
An organism that uses an inorganic chemical as an energy source and CO2 as a carbon source.
chemoheterotroph
An organism that uses organic molecules as a source of carbon and energy.
Claisen condensation reaction
The carbonyl condensation reaction of two ester molecules to give a β-keto ester product.
coal
A solid, black fuel with high carbon content that is the product of the decomposition of ancient plant material.
coke
A solid formed by heating coal in the absence of air that consists primarily of carbon and ash.
combustion analysis
A method of obtaining empirical formulas for unknown compounds, especially those containing carbon and hydrogen, by burning a sample of the compound in pure oxygen and analyzing the products of the combustion reaction.
Condensed structures
A shorthand way of writing structures in which carbon–hydrogen and carbon–carbon bonds are understood rather than shown explicitly. Propane, for example, has the condensed structure CH3CH2CH3.
Conjugate addition
Addition of a nucleophile to the b carbon atom of an a,b-unsaturated carbonyl compound.
covalent carbides
Binary compounds composed of carbon combined with low-electronegativity nonmetals or metalloids.
Cycloalkane
An alkane that contains a ring of carbons.
d-isomer
Arrangement of four different atoms or groups around a carbon atom. See l-isomer.
DEPT-NMR
An NMR method for distinguishing among signals due to CH3, CH2, CH, and quaternary carbons. That is, the number of hydrogens attached to each carbon can be determined.
diamond
An elemental form of carbon in which each carbon atom is covalently bonded to four other carbon atoms at the corners of a tetrahedron.
Dihedral angle
The angle between two bonds on adjacent carbons as viewed along the C-C bond.
E geometry
A term used to describe the stereochemistry of a carbon–carbon double bond. The two groups on each carbon are ranked according to the Cahn–Ingold–Prelog sequence rules, and the two carbons are compared. If the higherranked groups on each carbon are on opposite sides of the double bond, the bond has E geometry.
Eclipsed conformation
The geometric arrangement around a carbon–carbon single bond in which the bonds to substituents on one carbon are parallel to the bonds to substituents on the neighboring carbon as viewed in a Newman projection.
Electrophilic addition reactions
Addition of an electrophile to a carbon–carbon double bond to yield a saturated product.
Enol
A vinylic alcohol that is in equilibrium with a carbonyl compound, C=C-OH.
fullerenes
Carbon clusters, such as C₆₀, bonded in roughly spherical shapes containing from 36 to over 100 carbon atoms.
graphene
A new material that consists of a single sheet of carbon atoms (similar to a sheet from graphite) one atom thick.
graphite
An elemental form of carbon consisting of flat sheets of carbon atoms, bonded together as interconnected hexagonal rings held together by intermolecular forces, that can easily slide past each other.
Heat of hydrogenation
The amount of heat released when a carbon–carbon double bond is hydrogenated.
Hemiacetal
A functional group having one -OR and one -OH group bonded to the same carbon.
Heterocycle
A cyclic molecule whose ring contains more than one kind of atom. For example, pyridine is a heterocycle that contains ive carbon atoms and one nitrogen atom in its ring.
Hill reaction
The evolution of oxygen and photoreduction of an artificial electron acceptor by a chloroplast preparation in the absence of carbon dioxide.
indirect calorimetry
A method to estimate whole-body energy expenditure that is based on measuring the amount of oxygen used and carbon dioxide produced during energy metabolism.
inorganic compound
A small molecule that does not contain carbon and hydrogen.
ionic carbides
Binary compounds composed of carbon combined with low-electronegativity metals.
Keto–enol tautomerism
The equilibration between a carbonyl form and vinylic alcohol form of a molecule.
l-isomer
Arrangement of four different atoms or groups around a carbon atom. See d-isomer.
LDA
Lithium diisopropylamide, LiN(i-C3H7)2, a strong base commonly used to convert carbonyl compounds into their enolate ions.
Markovnikov’s rule
A guide for determining the regiochemistry (orientation) of electrophilic addition reactions. In the addition of HX to an alkene, the hydrogen atom bonds to the alkene carbon that has fewer alkyl substituents.
McLaferty rearrangement
A mass-spectral fragmentation pathway for carbonyl compounds.
metallic carbides
Binary compounds composed of carbon combined with metals that have a metallic lattice with holes small enough to fit carbon atoms.
Michael reaction
The conjugate addition reaction of an enolate ion to an unsaturated carbonyl compound.
n+1 rule
A hydrogen with n other hydrogens on neighboring carbons shows n 1 1 peaks in its 1H NMR spectrum.
Newman projection
A means of indicating stereochemical relationships between substituent groups on neighboring carbons. The carbon–carbon bond is viewed end-on, and the carbons are indicated by a circle. Bonds radiating from the center of the circle are attached to the front carbon, and bonds radiating from the edge of the circle are attached to the rear carbon.
Nucleophilic acyl substitution reaction
A reaction in which a nucleophile attacks a carbonyl compound and substitutes for a leaving group bonded to the carbonyl carbon.
Nucleophilic substitution reactions
Reactions in which one nucleophile replaces another attached to a saturated carbon atom.
organic matrix
The carboncontaining material between cells or within the mitochondria.
Organohalides
Compounds that contain one or more halogen atoms bonded to carbon.
Organometallic compound
A compound that contains a carbon–metal bond. Grignard reagents, RMgX, are examples.
photoautotroph
An organism that uses light as its energy source and carbon dioxide (CO2) as its carbon source.
photoheterotroph
An organism that uses light as its energy source and an organic carbon source.
Polycarbonates
Polyesters in which the carbonyl groups are linked to two -OR groups, [O=C(OR)2].
primary producer
An autotrophic organism, either chemotroph or phototroph, that converts carbon dioxide into organic compounds.
Redfield ratio
Atomic ratio of carbon nitrogen and phosphorus in marine phytoplankton.
respiratory exchange ratio (RER)
The ratio of carbon dioxide expired to oxygen consumed at the level of the lungs.
retinal
A 20-carbon isoprene aldehyde derived from carotene, which serves as the light-sensitive component of the visual pigment rhodopsin. Illumination converts 11-cis-retinal to all-trans-retinal.
saturated hydrocarbon
A hydrocarbon that is saturated (loaded to capacity) with hydrogen; a hydrocarbon containing no double bonds in the carbon chain.
Sequence rules
A series of rules for assigning relative rankings to substituent groups on a double-bond carbon atom or on a chirality center.
skeletal structures
A shorthand way of writing structures in which carbon atoms are assumed to be at each intersection of two lines (bonds) and at the end of each line.
soot
An amorphous form of carbon that forms during the incomplete combustion of hydrocarbons.
Staggered conformation
The three-dimensional arrangement of atoms around a carbon–carbon single bond in which the bonds on one carbon bisect the bond angles on the second carbon as viewed end-on.
Stork reaction
The conjugate addition of an enamine to an α,β-unsaturated carbonyl compound, followed by hydrolysis to yield a 1,5-dicarbonyl product.
Straight-chain alkanes
Alkanes whose carbon atoms are connected without branching.
Syn periplanar
Describing a stereo chemical relationship in which two bonds on adjacent carbons lie in the same plane and are eclipsed.
Urethane
A functional group in which a carbonyl group is bonded to both an -OR and an -NR2.
Vinylic
A term that refers to a substituent at a double-bond carbon atom. For example, chloroethylene is a vinylic chloride, and enols are vinylic alcohols.
washing soda
The hydrated crystal of sodium carbonate, Na2CO3 · 10 H2O.
Z geometry
A term used to describe the stereochemistry of a carbon–carbon double bond. The two groups on each carbon are ranked according to the Cahn–Ingold–Prelog sequence rules, and the two carbons are compared. If the higher ranked groups on each carbon are on the same side of the double bond, the bond has Z geometry.
α-Carbon
The carbon next to the carboxyl carbon.
α-Position
The position next to a carbonyl group.
α-Substitution reaction
The substitution of the a hydrogen atom of a carbonyl compound by reaction with an electrophile.
