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Direct alkylation of N,N-dialkyl benzamides with methyl sulfides under transition metal-free conditions.

ABSTRACT: Amides are a fundamental and widespread functional group, and are usually considered as poor electrophiles owing to resonance stabilization of the amide bond. Various approaches have been developed to address challenges in amide transformations. Nonetheless, most methods use activated amides, organometallic reagents or transition metal catalysts. Here, we report the direct alkylation of N,N-dialkyl benzamides with methyl sulfides promoted by the readily available base LDA (lithium diisopropylamide). This approach successfully achieves an efficient and selective synthesis of α-sulfenylated ketones without using transition-metal catalysts or organometallic reagents. Preliminary mechanism studies reveal that the deprotonative aroylation of methyl sulfides is promoted by the directed ortho-lithiation of the tertiary benzamide with LDA.

SUBMITTER: Bao CC

PROVIDER: S-EPMC9814863 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Direct alkylation of N,N-dialkyl benzamides with methyl sulfides under transition metal-free conditions.

Bao Can-Can CC Du Hui-Zhen HZ Luo Yan-Long YL Guan Bing-Tao BT

Communications chemistry 20210927 1

Amides are a fundamental and widespread functional group, and are usually considered as poor electrophiles owing to resonance stabilization of the amide bond. Various approaches have been developed to address challenges in amide transformations. Nonetheless, most methods use activated amides, organometallic reagents or transition metal catalysts. Here, we report the direct alkylation of N,N-dialkyl benzamides with methyl sulfides promoted by the readily available base LDA (lithium diisopropylami ...[more]

PMID: 36697564

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