Metalation of enamines

The metalation of enamines is a synthetically important process that has been modeled by the reaction of LiH with viny-lamine, CH2=CHNH2. The model reaction involves prior coordination of LiH with the nitrogen lone pair followed by a six-membered ring transition structure to give the 0-lithiated product (Figure 5). The alternative a-lithiation involves structures of higher energy. 

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