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A selective removal of the secondary hydroxy group from ortho-dithioacetal-substituted diarylmethanols.

ABSTRACT: We present a successful deoxygenation reaction of ortho-1,3-dithianylaryl(aryl)methanols which enables a selective removal of the secondary hydroxy group in presence of the 1,3-dithianyl moiety under reductive conditions. This reaction proceeds well with ZnI₂/Na(CN)BH₃ in dichloroethane or benzene for both unsubstituted and substituted aryls (by electron-rich groups). This is leading to formyl-protected diarylmethanes with potential application in the synthesis of new pharmaceuticals and optoelectronic materials. This synthetic approach gives an access to a wide variety of functionalized ortho-1,3-dithianylaryl(aryl)methanes in 26-95% yields and is recommended for the substrates containing sulfur atoms, for which transition metal-induced reactions fail.

SUBMITTER: Czarnecka A

PROVIDER: S-EPMC6009171 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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A selective removal of the secondary hydroxy group from ortho-dithioacetal-substituted diarylmethanols.

Czarnecka Anna A Kowalska Emilia E Bodzioch Agnieszka A Skalik Joanna J Koprowski Marek M Owsianik Krzysztof K Bałczewski Piotr P

Beilstein journal of organic chemistry 20180529

We present a successful deoxygenation reaction of ortho-1,3-dithianylaryl(aryl)methanols which enables a selective removal of the secondary hydroxy group in presence of the 1,3-dithianyl moiety under reductive conditions. This reaction proceeds well with ZnI2/Na(CN)BH3 in dichloroethane or benzene for both unsubstituted and substituted aryls (by electron-rich groups). This is leading to formyl-protected diarylmethanes with potential application in the synthesis of ne ...[more]

PMID: 29977391

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