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A cheap metal catalyzed ring expansion/cross-coupling cascade: a new route to functionalized medium-sized and macrolactones.

ABSTRACT: An efficient alkoxyl radical-triggered ring expansion/cross-coupling cascade was developed under cheap metal catalysis. Through the metal-catalyzed radical relay strategy, a wide range of medium-sized lactones (9-11 membered) and macrolactones (12, 13, 15, 18, and 19-membered) were constructed in moderate to good yields, along with diverse functional groups including CN, N₃, SCN, and X groups installed concurrently. Density functional theory (DFT) calculations revealed that reductive elimination of the cycloalkyl-Cu(iii) species is a more favorable reaction pathway for the cross-coupling step. Based on the results of experiments and DFT, a Cu(i)/Cu(ii)/Cu(iii) catalytic cycle is proposed for this tandem reaction.

SUBMITTER: Liu S

PROVIDER: S-EPMC10189895 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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A cheap metal catalyzed ring expansion/cross-coupling cascade: a new route to functionalized medium-sized and macrolactones.

Liu Shuai S Ma Pengchen P Zhang Lu L Shen Shenyu S Miao Hong-Jie HJ Liu Le L Houk K N KN Duan Xin-Hua XH Guo Li-Na LN

Chemical science 20230417 19

An efficient alkoxyl radical-triggered ring expansion/cross-coupling cascade was developed under cheap metal catalysis. Through the metal-catalyzed radical relay strategy, a wide range of medium-sized lactones (9-11 membered) and macrolactones (12, 13, 15, 18, and 19-membered) were constructed in moderate to good yields, along with diverse functional groups including CN, N<sub>3</sub>, SCN, and X groups installed concurrently. Density functional theory (DFT) calculations revealed that reductive ...[more]

PMID: 37206389

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