Formation of Unexpected Heterocyclic Products from Pyrolysis of Thiocarbonyl Stabilised Phosphonium Ylides

Phosphonium salts and P-ylides

“…Aikten et al described the pyrolysis of chiral phthalimido thioxostabilised phosphonium ylides. 293 Such compounds were prepared from (S)-alanine and (S)-phenylalanine, and underwent an intramolecular Wittig reaction leading to pyrrolo[2,1-a]isoindol-5-one-2-thiones, rather than the expected P to S migration of a phenyl group (Scheme 14).…”