One-pot synthesis of 3-trifluoromethylbenzo[ b ][1,4]oxazines from CF 3 -imidoyl sulfoxonium ylides with 2-bromophenols.

Herein, a method to access 3-trifluoromethyl-1,4-benzoxazines from CF 3 -imidoyl sulfoxonium ylides and 2-bromophenols has been demonstrated. This synthetic protocol proceeds via a one-pot two-step sequence that includes the lithium-bromide-promoted O-H insertion of sulfoxonium ylides and annulation, and has the merits of broad substrate scope, excellent functional tolerance and operational simplicity, which provides an alternative means of obtaining CF 3 -substituted heterocycles.