621-06-7Relevant articles and documents
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Watanabe et al.
, p. 1869 (1979)
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Efficient and accessible silane-mediated direct amide coupling of carboxylic acids and amines
D'Amaral, Melissa C.,Jamkhou, Nick,Adler, Marc J.
supporting information, p. 288 - 295 (2021/01/28)
A straightforward method for the direct synthesis of amides from amines and carboxylic acids without exclusion of air or moisture using diphenylsilane with N-methylpyrrolidine has been developed. Various amides are made efficiently, and broad functional group compatibility is shown through a Glorius robustness study. A gram-scale synthesis demonstrates the scalability of this method. This journal is
Photocatalyzed Triplet Sensitization of Oximes Using Visible Light Provides a Route to Nonclassical Beckmann Rearrangement Products
Zhang, Xiao,Rovis, Tomislav
, p. 21211 - 21217 (2021/12/27)
Oximes are valuable synthetic intermediates for the preparation of a variety of functional groups. To date, the stereoselective synthesis of oximes remains a major challenge, as most current synthetic methods either provide mixtures of E and Z isomers or furnish the thermodynamically preferred E isomer. Herein we report a mild and general method to achieve Z isomers of aryl oximes by photoisomerization of oximes via visible-light-mediated energy transfer (EnT) catalysis. Facile access to (Z)-oximes provides opportunities to achieve regio- and chemoselectivity complementary to those of widely used transformations employing oxime starting materials. We show an enhanced one-pot protocol for photocatalyzed oxime isomerization and subsequent Beckmann rearrangement that enables novel reactivity with alkyl groups migrating preferentially over aryl groups, reversing the regioselectivity of the traditional Beckmann reaction. Chemodivergent N- or O- cyclizations of alkenyl oximes are also demonstrated, leading to nitrones or cyclic oxime ethers, respectively.
