[3,3]-Sigmatropic rearrangement of boronated allylcyanates: a new route to α-aminoboronate derivatives and trisubstituted tetrahydrofurans.

ABSTRACT

[3,3]-Sigmatropic cyanate-isocyanate rearrangement provides a powerful tool for the preparation of α-isocyanato allylboronic esters, which can be further trapped with a variety of nucleophiles. Hydrogenation gave the corresponding α-aminoboronates derivatives while addition of aldehydes afforded homoallylic alcohols, (tetrahydrofuran-2-yl)carbamate, ether, or urea derivatives.