ChemInform Abstract: Unexpected High Regiocontrol in Heck Reaction of Fluorine‐Containing Electron‐Deficient Olefins — Highly Regio‐ and Stereoselective Synthesis of β‐Fluoroalkyl‐α‐aryl‐α,β‐unsaturated Ketones.

Abstract

Synthesis of β-Fluoroalkyl-α-aryl-α,β-unsaturated Ketones. -Treatment of trifluoroarylbutenones (I) with aryldiazonium salts (II) and (VI) gives rise to α-arylated Heck adducts (III)/(IV) and (VII)/(VIII) besides the Michael adducts (V) and (IX). Aryldiazonium salts bearing an electron-donating group or halogens at the ortho, meta or para position participate well in the reaction, affording the (Z)-isomer preferentially. In contrast, aryldiazonium salts possessing an electron-withdrawing group, as well as bulky salts do not afford satisfactory results.