Synthesis of Morita-Baylis-Hillman-fluorides using 1,1,2,2-tetrafluoroethyl-N,N-dimethylamine

Morita-Baylis-Hillman (MBH)-fluorides are valuable platforms for asymmetric allylic substitution reactions. However, the preparation of MBH-fluorides requires the use of an explosive fluorinating reagent, namely (diethylamino)sulfur trifluoride (DAST). Thus, we herein report a safe, alternative method for the preparation of MBH-fluorides via the deoxyfluorination of MBH-alcohols using 1,1,2,2-tetrafluoroethyl-N,N-dimethylamine (TFEDMA). Accordingly, a variety of MBH-alcohols were smoothly converted to their corresponding MBH-fluorides in moderate to good yields without the requirement for an activator. This fluorination reaction was found to proceed via an S(N)1 process involving a stable allylic cation intermediate. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

A safe alternative method for the preparation of MBH-fluorides via deoxyfluorination of MBH-alcohols using TFEDMA was reported, which does not require an activator and successfully converts various MBH-alcohols to MBH-fluorides in moderate to good yields. The fluorination reaction proceeds via an S(N)1 process involving a stable allylic cation intermediate.