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Catalyst-free reductive cyclization of bis(2-aminophenyl) disulfide with CO₂ in the presence of BH₃NH₃ to synthesize 2-unsubstituted benzothiazole derivatives.

ABSTRACT: An efficient and catalyst-free methodology for the reductive cyclization of various disulfides using BH₃NH₃ as a reductant and CO₂ as a C1 resource was developed. The desired 2-unsubstituted benzothiazole derivatives were obtained in good to excellent yields. Moreover, mechanism investigation demonstrated that BH₃NH₃ played an important role in the formation of benzothiazole. As a reducing agent, BH₃NH₃ reduced CO₂ and cleaved the S-S bond of the disulfide efficiently. In addition, the N-H bond of the amino group was also activated by BH₃NH₃. To the best of our knowledge, this is an unprecedented catalyst-free protocol for the synthesis of 2-unsubstituted benzothiazole from bis(2-aminophenyl) disulfide and CO₂.

SUBMITTER: Li X

PROVIDER: S-EPMC9208316 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Catalyst-free reductive cyclization of bis(2-aminophenyl) disulfide with CO2 in the presence of BH3NH3 to synthesize 2-unsubstituted benzothiazole derivatives.

Li Xiao X Liu Zhenbao Z Hong Hailong H Han Limin L Zhu Ning N

RSC advances 20220620 28

An efficient and catalyst-free methodology for the reductive cyclization of various disulfides using BH3NH3 as a reductant and CO2 as a C1 resource was developed. The desired 2-unsubstituted benzothiazole derivatives were obtained in good to excellent yields. Moreover, mechanism investigation demonstrated that BH3NH3 played an important role in the formation of benzothiazole. As a reducing agent, BH3NH3 reduced CO2 ...[more]

PMID: 35800324

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