Choose the correct option.14.How many electrons are present in the nonbonding π molecular orbital of the allyl anion?A)0B)1C)2D)3E)415.Which of the following statements concerning electrocyclic reactions is correct?A)The ground state HOMO of a compound with an even number of conjugated double bonds is asymmetric.B)The allowed mode of ring closure under thermal conditions for a molecule containing an even number of conjugated double bonds is disrotatory.C)The allowed mode of ring closure under photochemical conditions for a molecule containing an odd number of conjugated double bonds is disrotatory.D)both B and CE)none of the above16.Under thermal conditions,(2E,4Z)-hexadiene undergoes a ___ ring closure to yield ___.A)conrotatory,cis-3,4-dimethylcyclobuteneB)conrotatory,trans-3,4-dimethylcyclobuteneC)disrotatory,cis-3,4-dimethylcyclobuteneD)disrotatory,trans-3,4-dimethylcyclobutene17.Under photochemical conditions,(2E,4Z)-hexadiene undergoes a ___ ring closure to yield ___.A)conrotatory,cis-3,4-dimethylcyclobuteneB)conrotatory,trans-3,4-dimethylcyclobuteneC)disrotatory,cis-3,4-dimethylcyclobuteneD)disrotatory,trans-3,4-dimethylcyclobutene18.Under thermal conditions,(2E,4E)-hexadiene undergoes a ___ ring closure to yield ___.A)conrotatory,cis-3,4-dimethylcyclobuteneB)conrotatory,trans-3,4-dimethylcyclobuteneC)disrotatory,cis-3,4-dimethylcyclobuteneD)disrotatory,trans-3,4-dimethylcyclobutene19.Under photochemical conditions,(2E,4E)-hexadiene undergoes a ___ ring closure to yield ___.A)conrotatory,cis-3,4-dimethylcyclobuteneB)conrotatory,trans-3,4-dimethylcyclobuteneC)disrotatory,cis-3,4-dimethylcyclobuteneD)disrotatory,trans-3,4-dimethylcyclobutene20.Which of the following statements best describes the term suprafacial?A)formation of two sigma bonds from the same side of the pi systemB)formation of two pi bonds from the same side of the sigma systemC)formation of two sigma bonds from opposite sides of the pi systemD)formation of two pi bonds from opposite sides of the sigma systemE)an anti cycloaddition21.Which of the following ring formations must involve a suprafacial bond formation?A)four-membered ringB)five-membered ringC)six-membered ringD)A and CE)A,B and C22.Which of the following statements about carbon migrations is correct?A)Carbon migrations never occur by a sigmatropic rearrangement.B)Under thermal conditions,a [1,3] carbon migration that occurs suprafacially must also occur with inversion of configuration at the migrating carbon.C)Under thermal conditions,a [1,5] carbon migration that occurs suprafacially must also occur with inversion of configuration at the migrating carbon.D)Under thermal conditions,a carbon migration that occurs suprafacially must occur with inversion no matter the system's symmetry.E)B,C,and D23.Under what conditions would a 1,3-hydrogen shift occur in a sigmatropic rearrangement?A)thermal conditionsB)photochemical conditionsC)suprafacial pathwayD)A and CE)B and C1.24.Describe a Cope rearrangement.A)[3,3] sigmatropic rearrangement of a 1,5-dieneB)[1,3] sigmatropic rearrangement of an alkeneC)[3,3] sigmatropic rearrangement of an allyl vinyl etherD)[1,5] sigmatropic rearrangement of a 1,3-dieneE)[2,3] sigmatropic rearrangement of an alkene25.Describe a Claisen rearrangement.A)[3,3] sigmatropic rearrangement of a 1,5-dieneB)[1,3] sigmatropic rearrangement of an alkeneC)[3,3] sigmatropic rearrangement of an allyl vinyl etherD)[1,5] sigmatropic rearrangement of a 1,3-dieneE)[2,3] sigmatropic rearrangement of an alkene26.Give the conditions for 1,3-hydrogen shifts.You may choose more than one answer.A)suprafacial rearrangementB)antarafacial rearrangementC)thermal conditionsD)photochemical conditionsE)all of the above27.Give the conditions for 1,5-hydrogen shifts.You may choose more than one answer.A)suprafacial rearrangementB)antarafacial rearrangementC)thermal conditionsD)photochemical conditionsE)all of the above28.Give the conditions for 1,7-hydrogen shifts.You may choose more than one answer.A)suprafacial rearrangementB)antarafacial rearrangementC)thermal conditionsD)photochemical conditionsE)all of the above29.Which of the following statements best describes what is meant by pericyclic reactions?A)reactions in which a nucleophile reacts with an electrophileB)reactions in which an electrophile reacts with a nucleophileC)reactions in which a free radical reacts with another free radicalD)oxidation-reduction reactions in which electrons are lost or gainedE)reactions that occur as a result of a cyclic reorganization of electrons

Question

Accepted Answer

Since you have posted multiple independent questions in the same request, we will solve the first…

.How many electrons are present in the nonbonding π molecular orbital of the allyl anion? A)0