JEE MAIN - Chemistry (2006 - No. 15)
Reaction of trans-2-phenyl-1-bromocyclopentane on reaction with alcoholic KOH produces
4-phenylcyclopentene
2-phenylcyclopentene
1-phenylcyclopentene
3-phenylcyclopentene
Explication
Hughes and Ingold proposed that bimolecular elimination
reactions take place when the two groups to be eliminated are
trans and lie in one plane with the two carbon atoms to which
they are attached i.e. E2 reactions are stereoselectively trans.