Since Z enolates must react through a transition state which either contains a destabilizing syn-pentane interaction or anti-Felkin rotamer, Z-enolates exhibit lower levels of diastereoselectivity in this case.

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Since Z enolates must react through a transition state which either contains a destabilizing syn-pentane interaction or anti-Felkin rotamer, Z-enolates exhibit lower levels of diastereoselectivity in this case.