(I) Give the decreasing order of SN^2 reacivity of the following alkoxide nucleophile. Me_3 CO^(Ө), MeCH_2O^(Ө), Me_2CHO^(Ө) and (b) .

(I) Give the decreasing order of SN^2 reacivity of the following alkox

1.	(I) Give the decreasing order of SN^2 reacivity of the following alkoxide nucleophile. Me_3 CO^(Ө), MeCH_2O^(Ө), Me_2CHO^(Ө) and (b) .
Answer» Solution :(I) For solution, see to Section `11.17` (II) (a) is less REACTIVE than in both `SN^(1)` and `SN^2` reactions because the ion FORMED in the T.S. has more ring strain than the (B) The bridgehead halide in `(A)` is inert in both `SN^1` and `SN^2` reactions. A flat `R^(oplus)` cannot form at the bridgehead `C`, making `SN^1` impossible. Also three bridges prevent the back-side attrack for `SN^2` reaction and inversion is also impossible. `(B)` is a typical `3^@` halide and reacts via `SN^1` and less by `SN^2`.