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N-Methylimidazole-catalyzed synthesis of carbamates from hydroxamic acids via the Lossen rearrangement.

ABSTRACT: An efficient, one-pot, N-methylimidazole (NMI) accelerated synthesis of aromatic and aliphatic carbamates via the Lossen rearrangement is reported. NMI is a catalyst for the conversion of isocyanate intermediates to the carbamates. Moreover, the utility of arylsulfonyl chloride in combination with NMI minimizes the formation of often-observed hydroxamate-isocyanate dimers during the sequence. Under the present conditions, lowering of temperatures is also possible, enabling a mild protocol.

SUBMITTER: Yoganathan S

PROVIDER: S-EPMC3563000 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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N-Methylimidazole-catalyzed synthesis of carbamates from hydroxamic acids via the Lossen rearrangement.

Yoganathan Sabesan S Miller Scott J SJ

Organic letters 20130117 3

An efficient, one-pot, N-methylimidazole (NMI) accelerated synthesis of aromatic and aliphatic carbamates via the Lossen rearrangement is reported. NMI is a catalyst for the conversion of isocyanate intermediates to the carbamates. Moreover, the utility of arylsulfonyl chloride in combination with NMI minimizes the formation of often-observed hydroxamate-isocyanate dimers during the sequence. Under the present conditions, lowering of temperatures is also possible, enabling a mild protocol. ...[more]

PMID: 23327543

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