Question
The missing reagents $${R_1}$$ and $${R_2}$$ in the following series of reactions are \[C{{H}_{3}}C{{H}_{2}}Br\xrightarrow{{{R}_{1}}}\left[ \,\,\,\, \right]\xrightarrow{{{R}_{2}}}C{{H}_{3}}\overset{-}{\mathop{C}}\,H{{P}^{+}}P{{h}_{3}}\]
A.
$$PhLi$$ and $$P{h_3}P$$ respectively
B.
$$P{h_3}P$$ and $$PhLi$$ respectively
C.
$$P{h_3}P$$ and $${C_2}{H_5}ONa$$ respectively
D.
Either (B) or (C)
Answer :
Either (B) or (C)
Solution :
\[C{{H}_{3}}C{{H}_{2}}Br+P{{h}_{3}}P\to \] \[C{{H}_{3}}C{{H}_{2}}{{P}^{+}}P{{h}_{3}}B{{r}^{-}}\xrightarrow[{{C}_{2}}{{H}_{5}}ONa]{{{C}_{6}}{{H}_{5}}Li\,\,\text{or}}\] \[C{{H}_{3}}CH=PP{{h}_{3}}\underset{{}}{\overset{{}}{\longleftrightarrow}}C{{H}_{3}}\overset{-}{\mathop{C}}\,H\overset{+}{\mathop{P}}\,P{{h}_{3}}\]