An addition/ring-opening reaction of aryl-and alkenylboronic acids to cyclobutanones took place in 1, 4-dioxane at 100° C in the presence of a rhodium (I) catalyst bearing tri-t- butylphosphine, affording ring-opened ketones. Mechanistically, the reaction proceeded through the addition of an organorhodium species to the carbonyl group of a cyclobutanone and a subsequent ring-opening of the resulting rhodium cyclobutanolate through β-carbon ...
