2-Azapentadienyl anion reaction with carbonyl compounds

Azapentadienyl anion (31), readily prepared by deprotonation of the /V-allylimine, reacts with carbonyl compounds at either the a- or the 7-position (equation 10). The regioselectivity depends upon the reaction conditions. 1-Azapentadienyl anion (32 equation 11), prepared from the cyclohexylimine of ti-glaldehyde and LDA, reacts with aldehydes and ketones to give the 7-capture products in the presence of HMPA or the a-capture products in the absence of HMPA. ... 

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