Enantioselective Synthesis of 3-Methyleneindan-1-ols via a One-Pot Allylboration–Heck Reaction of 2-Bromobenzaldehydes
摘要:
A novel, one-pot allylboration-Heck reaction of 2-bromobenzaldehydes has been developed for the general and efficient synthesis of 3-methyleneindan-1-ols. Modification of the one-pot procedure to include chiral Bronsted acid catalyzed allylation has allowed the preparation of these building blocks in high enantioselectivity and excellent yields.
Electrophilic Activation of Benzaldehydes through<i>ortho</i> Palladation: One-Pot Synthesis of 3-Methylene-indan-1-ols through a Domino Allylstannylation/Heck Reaction under Neutral Conditions
Active neighbors: The Pd‐catalyzed reaction of ortho‐iodo‐ and ortho‐trifluoromethanesulfonyloxy(OTf)benzaldehydes with allyltributylstannane gives 3‐alkylidene‐1‐indanols (see scheme). The allylation/Heckreaction involves a new catalytic activation mode: the electrophilicactivation of an aldehyde group by a Lewis acidic PdII center generated at the ortho position by oxidative addition. Alkoxystannanes