Synthesis with 1,2‐Oxazines. II. Synthesis and Properties of 2,3‐dimethyl‐5,6‐dihydro‐4H‐1,2‐oxaziniumiodide

Preparation of 2,3‐Dimethyl‐5,6‐dihydro‐4H‐1,2‐oxaziniumiodide was achieved by N‐alkylation of 3‐methyl‐5,6‐dihydro‐4H‐1,2‐oxazine. Reactions with C‐nucleophiles led to the corresponding N‐methyl‐perhydro‐1,2‐oxazine derivatives. Reaction with sodium hydride in triglyme led to 3‐methyl‐4‐aza‐1,3‐pentadiene.