Amides stereoselective conjugate reduction

Unlike with sodium borohydride (see Section 11.01.5.2), pyrrolizin-3-one 2 reacts with lithium aluminohydride mainly as an amide. No conjugate addition occurs, and only the reductive lactam cleavage takes place to give stereoselectively the (Z)-allylie alcohol 77. Similarly, benzo-annulated pyrrolizin-3-one 17 gives the corresponding benzylic alcohol 78. The same reactivity was observed with organometallics such as methyllithium which gives exclusively the tertiary (Z)-allylic alcohol 79 (Scheme 7). 

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