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DOI: 10.1055/sos-SD-104-00395

Delvos, L. B.; Oestreich, M.Science of Synthesis Knowledge Updates, (2017168.

Amino-substituted chloroboranes 2 are substituted by equimolar amounts of silyllithium reagents 1 to generate Si—B interelement compounds 3 in acceptable to good yields (Scheme 8).[‌30‌‌34‌] The amino substituents at the boron atom are essential for the stability of the Si—B bond and prevent borate formation by twofold addition of the silicon nucleophile. Replacement of one amino group with a butyl substituent is tolerated, but with two butyl groups on the boron atom the reaction is not successful. The reaction also proceeds with trimethylsilyllithium[‌32‌] or triethylsilyllithium[‌33‌] (not shown) but, unlike their aryl-substituted derivatives 1, these reagents cannot be accessed by simple reductive metalation of the parent chlorosilane with lithium metal. Instead, less-attractive bis(triorganosilyl)mercury precursors are required. These silylboron compounds are highly moisture-sensitive, and that somewhat limits their further synthetic use. However, these compounds are valuable building blocks for the preparation of more stable silylboronic esters by ligand exchange at the boron subunit (see Section

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