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Please login or sign up for a free trial to access the full content. Variation 2: Lossen Rearrangement

DOI: 10.1055/sos-SD-040-00241

Purchase, R.; Sainsbury, M.Science of Synthesis, (200940401.

In the classical Lossen procedure[‌231‌] an acylhydroxamic acid 186 (R2=H)[‌232‌] is converted into an isocyanate 187 by base treatment; however, as the reaction is normally carried out in water the isocyanate immediately undergoes hydrolysis to give a primary amine 188 containing one less carbon atom than the starting material (Scheme 59).[‌28‌,‌233‌,‌234‌]

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