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Please login to access the full content or check if you have access via Method 15: Lossen Rearrangement

DOI: 10.1055/sos-SD-018-00070

Braverman, S.; Cherkinsky, M.; Birsa, M. L.Science of Synthesis, (200518133.

The Lossen rearrangement, involving decomposition of hydroxamic acids or their acyl derivatives when they are treated with base or sometimes even just on heating, has also found some utility for the synthesis of isocyanates. Thus pyrolysis of several benzhydroxamic chlorides 190 at 180°C gives aryl isocyanates in moderate yields (Scheme 102).[‌467‌]

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