Catalytic Addition of Secondary Amines to Carbodiimides by a Half-Sandwich Yttrium Complex: An Efficient Route to N,N′,N′′,N′′-Tetra­substituted Guanidines

Abstract

The catalytic addition of secondary amines to carbodiimides has been achieved by use of an yttrium half-sandwich alkyl complex {Me₂Si(C₅Me₄)(NPh)}Y(CH₂SiMe₃)(THF)₂, which offers a straightforward, atom-economical route to tetrasubstituted guanidines. An yttrium guanidinate species has been confirmed to be a true catalytic species in this reaction.

Key words

yttrium - catalytic addition - amines - carbodiimides - guanidines - guanidinates

References and Notes

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