Enantioselective Construction of Indanones from Cyclobutanols Using a Rhodium-Catalyzed C-C/C-H/C-C Bond Activation Process
作者:Nicolai Cramer、Tobias Seiser、Gino Cathomen
DOI:10.1055/s-0029-1219959
日期:2010.7
Enantioselective rhodium(I)-catalyzed reactions of tert-cyclobutanols lead via consecutive C-C/C-H/C-C bond activations to indanones with quaternary stereogenic centers.
describe the unexpected 2-fold Csp3–Csp3 bond cleavage suffered by cyclobutanols in the presence of a catalytic amount of Pd(OAc)2 and promoted by the bulky biaryl JohnPhos ligand. Overall, the sequential cleavage of a strained and an unstrained Csp3–Csp3 bond leads to the formal [2 + 2]-retrocyclization products, namely, styrene and acetophenone derivatives. This procedure might enable the use of cyclobutanols