Synthesis of -Alkenylated Heterocycles via TP-Promoted Condensation with Ketones.

Herein, we describe a convenient protocol for the synthesis of -alkenylated heterocycles using abundant ketone electrophiles and TP as a water scavenger under microwave irradiation. The method can be applied to a diverse range of -heterocycles and ketones with good to excellent yields (up to 94%). This procedure is particularly attractive, as it is metal- and base-free, tolerates a variety of functional groups, and offers ease of product purification. The utility of the protocol was exemplified by synthesizing pharmaceutically relevant scaffolds containing the -alkenyl motif and was further extended to a one-pot reductive amination sequence.