Dramatic Effect of Boron-Based Lewis Acids in Cross-Metathesis Reactions

Abstract

Amino compounds such as allylic carbamates or amides are poor partners in cross-metathesis reactions because of possible coordination of the emerging carbene to the polar functional group. Whereas the use of titanium Lewis acid catalysts was unsatisfactory, an impressive increase in yields was obtained with boron-based Lewis acids.

cross-metathesis - Lewis acid - amino compounds - boron - ruthenium

References

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8

Usually CM coupling requires two or three equivalents of one partner. Although use of more than one equivalent of one of the olefin partner slightly improves the yield of the coupling.

Isomerization is currently observed for metathesis of nitrogen derivatives. For recent examples, see:

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