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Stable Boron Dithiolene Radicals.

ABSTRACT: Whereas low-temperature (-78?°C) reaction of the lithium dithiolene radical 1. with boron bromide gives the dibromoboron dithiolene radical 2. , the parallel reaction of 1. with (C6 H11 )2 BCl (0?°C) affords the dicyclohexylboron dithiolene radical 3. . Radicals 2. and 3. were characterized by single-crystal X-ray diffraction, UV/Vis, and EPR spectroscopy. The nature of these radicals was also probed computationally. Under mild conditions, 3. undergoes unexpected thiourea-mediated B-C bond activation to give zwitterion 4, which may be regarded as an anionic dithiolene-modified carbene complex of the sulfenyl cation RS+ (R=cyclohexyl).

SUBMITTER: Wang Y

PROVIDER: S-EPMC7679077 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Stable Boron Dithiolene Radicals.

Wang Yuzhong Y Xie Yaoming Y Wei Pingrong P Blair Soshawn A SA Cui Dongtao D Johnson Michael K MK Schaefer Henry F HF Robinson Gregory H GH

Angewandte Chemie (International ed. in English) 20180522 26

Whereas low-temperature (-78 °C) reaction of the lithium dithiolene radical 1. with boron bromide gives the dibromoboron dithiolene radical 2. , the parallel reaction of 1. with (C6 H11 )2 BCl (0 °C) affords the dicyclohexylboron dithiolene radical 3. . Radicals 2. and 3. were characterized by single-crystal X-ray diffraction, UV/Vis, and EPR spectroscopy. The nature of these radicals was also prob ...[more]

PMID: 29756257

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