C-P bond fonnation

Recent Advances in Metal-Catalyzed C-P Bond Fonnation... 

The difference in reaction rate results from different degrees of tt bond development in the E2 transition state. Since tt overlap of p orbitals requires theh axes to be parallel, tt bond fonnation is best achieved when the four atoms of the H—C—C—X unit lie in the same plane at the transition state. The two confonnations that permit this are termed syn coplanar and anti coplanar. 

C-C bond fonnation between A(-Eoc-protected imines and p-keto acetyloxazolidinone [86], Excellent results were obtained with imines bearing either an electron-withdrawing or an electron-donating aryl group. Furthermore, the outlined protocol tolerated p-keto acetyloxazolidinone with different aliphatic substiments. Although longer reaction times were required, no adverse effect on neither the diaste-reo- nor enantioselectivity could be detected (Scheme 11.25). 

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