Term
| Is the primary allylic carbon-hydrogen bond relatively strong or relatively weak? |
|
Definition
| relatively weak; only 87 kcal/mol |
|
|
Term
| Is the primary allylic carbon-hydrogen bond weaker or stronger than a tertiary C-H bond? |
|
Definition
|
|
Term
| Do allylic C-X bonds dissociate relatively fast or relatively slow under SN1 conditions? |
|
Definition
|
|
Term
| Is an allylic carbon more or less stable than other primary carbocations? |
|
Definition
|
|
Term
| What is the pKa of an allylic C-H bond? |
|
Definition
|
|
Term
| Is the formation of an allylic carbon anion favored or not? |
|
Definition
|
|
Term
|
Definition
| the carbon bonded to a carbon involved in an alkene functional group |
|
|
Term
| What is the major stabilizing force for allylic carbon forms? |
|
Definition
|
|
Term
| Each carbon in the allylic structure is _____ hybridized |
|
Definition
|
|
Term
|
Definition
| a pi orbital that has the same energy as a noninteracting p orbital |
|
|
Term
| The resonance formations for allylic systems indicate that it is mainly the two _____ carbons that accommodate the charges in the ions or the odd electron in the radical |
|
Definition
|
|
Term
| radical allylic bromination takes place when bromine levels are _____ |
|
Definition
|
|
Term
|
Definition
| two double bonds separated by one single bond; comes from the addition of a fourth p orbital; comes from the Latin word for union (conjugatio) |
|
|
Term
|
Definition
| two double bonds are separated by saturated carbons; in contrast with conjugated dienes |
|
|
Term
|
Definition
| pi bonds share a single sp hybridized carbon & are perpendicular to each other; in contrast with conjugated dienes |
|
|
Term
| noninteracting double bonds |
|
Definition
| separated by one or more saturated carbon atoms |
|
|
Term
|
Definition
| two pi bonds lie on the same side of the C2-C3 axis |
|
|
Term
|
Definition
| pi bonds are on opposite sides |
|
|
Term
| The prefix "s" in s-cis and s-trans refers to the fact that the bridge between C2 & C3 constitutes a _____ bond |
|
Definition
|
|
Term
| Are conjugated dienes more or less reactive kinetically in the presence of electrophiles/other reagents than dienes with isolated double bonds? |
|
Definition
|
|
Term
|
Definition
| when a ratio of products for a reaction reflects their thermodynamic stability |
|
|
Term
|
Definition
| when a ratio of products for a reaction reflects their relative rates of formation/relative heights of the respective activation barriers |
|
|
Term
| Will an irreversible reaction be under kinetic or thermodynamic control? |
|
Definition
|
|
Term
|
Definition
| when more than two double bonds are in conjugation |
|
|
Term
| Is benzene generally reactive? |
|
Definition
|
|
Term
|
Definition
| a conjugated diene adds to an alkene to yield cyclohexene derivatives |
|
|
Term
| What are the products of cycloaddition reactions called? |
|
Definition
|
|
Term
|
Definition
| the alkene in a Diels-Alder reaction |
|
|
Term
| Can rings be formed by the linkage of the termini of a single conjugated di-, tri-, or polyene? |
|
Definition
|
|
Term
|
Definition
| the formation of a ring by a Diels-Alder reaction occurring on a single molecule |
|
|
Term
|
Definition
| a class of transformations that exhibit transition states with a cyclic array of nuclei & electrons; ex) cycloadditions & electrocyclic reactions; comes from the Greek word "peri" for "around" |
|
|
Term
|
Definition
| using light to drive a reaction in the thermodynamically unfavorable direction |
|
|
Term
| Are electrocyclic reactions concerted and stereospecific? |
|
Definition
|
|
Term
|
Definition
| a process in which the carbon atoms are found to rotate in the same direction in a ring opening |
|
|
Term
|
Definition
| the photochemical closure of a diene ring; proceeds with stereochemistry exactly opposite that observed in thermal opening |
|
|
Term
|
Definition
| a process in which reacting carbons rotate in opposite directions |
|
|
Term
| If there are an even number of pairs of participating electrons in an electrocyclic reaction, will the thermal process be conrotatory or disrotatory? |
|
Definition
|
|
Term
| If there are an even number of pairs of participating electrons in an electrocyclic reaction, will the photochemical process be conrotatory or disrotatory? |
|
Definition
|
|
Term
| If there are an odd number of pairs of participating electrons in an electrocyclic reaction, will the thermal process be conrotatory or disrotatory? |
|
Definition
|
|
Term
| If there are an odd number of pairs of participating electrons in an electrocyclic reaction, will the photochemical process be conrotatory or disrotatory? |
|
Definition
|
|
Term
| What do the Woodward-Hoffman rules describe? |
|
Definition
| the stereochemical outcomes of electrocyclic reactions |
|
|
Term
|
Definition
| a process in which a rubber is treated with hot elemental sulfur to increase its elasticity |
|
|
