Solvomercuration-reduction, olefins

Solvomercuration of Olefins Hydration of C=C Double Bonds through Subsequent Reduction... 

Fig. 3.37. Hydration of a symmetric olefin through solvomercuration/ reduction.

Fig. 3.38. Regioselective hydration of an asymmetric olefin via solvomercuration/reduction.

Besides H20, simple alcohols or acetic acid can also be added to olefins by solvomercuration/reduction. Figure 3.39 shows MeOH addition as an example. The regioselec-tivities of this reaction and of the H20 addition in Figure 3.38 are identical. 

Fig. 3.39. Regioselective methanol addition to an asymmetric olefin via solvomercuration/ reduction.

Fig. 1.11. Net reaction (a) for the hydration of olefins (R = CH3, R = H) or (b) for the addition of alcohol to olefins (R = CF3, R = alkyl) via the reaction sequence (1) solvomercuration of the olefin (for mechanism, see Figure 3.37 regioselectivity Figure 3.38) (2) reduction of the alkylmercury compound obtained (for mechanism, see Figure 1.12).

Amides.1 The solvomercuration-demercuration of terminal olefins or cyclic olefins with acetonitrile and mercury 11) nitrate followed by reduction of the intermediate organomercury compound affords amides, hydrolyzable to amines. Neither mercuric acetate nor mercuric trifiuoroacetate is satisfactory in this reaction. Preliminary attempts to use a tertiary olefin failed. 

In contrast, the mercurial enones (89) (obtained by specific solvomercuration of the corresponding pendant terminal olefins) are isolated, and on treatment with sodium trimethoxyborohydride are reductively cyclized to (90). Alkynes... 

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