Question

Complete the following reactions:
`HC-=CHoverset(?)rarr(B)overset(?)rarr(C)overset(?)rarr(D)`
The compounds (E) to (F) can be obtained by four different reagents. Give the names of the reagents.

Answer 1

i. Preparation of (E) from (A): Introduction of two different groups (Et- and Pr-groups) is required in (A), which can be obtained by reacting A with `NaNH_2` and their reaction with `Et-Br` and again with `NaNH_2` and `Pr-Br`.
ii. Preparation of (G) from (E), Introduction of cyclopropyl ring can be achieved by carbene insertion to alkene. Therefore, the sequence should be:
`(E)rarrcis-Alken eoverset(CH_2N_2)underset( :CH_2)rarr(G)`
iii. Preparation of (J) from (E), It can be obtained by the same sequence as in (ii), but from trans-alkene. Therefore, the sequence should be:
`(E)rarrtrans-Alken eoverset(CH_2N_2)underset( :CH_2)rarr(J)`
Reactions:

Reactions of (E) with reagents (iii) and (iv):