Stereospecific conversion of alcohols into pinacol boronic esters using lithiation-borylation methodology with pinacolborane.
نویسندگان
چکیده
The synthesis of primary and secondary pinacol boronic esters via lithiation-borylation of carbamates and benzoates with pinacolborane is described. This new protocol enables the highly selective synthesis of enantioenriched and geometrically defined boronic esters that cannot otherwise be accessed by alternative methodologies.
منابع مشابه
Asymmetric synthesis of 1-heteroaryl-1-arylalkyl tertiary alcohols and 1-pyridyl-1-arylethanes by lithiation-borylation methodology.
The synthesis of highly enantioenriched α-heterocyclic tertiary alcohols has been achieved via lithiation-borylation of a configurationally stable lithiated carbamate and heterocyclic pinacol boronic esters followed by oxidation. Protodeboronation of the α-heterocyclic tertiary boronic esters using TBAF·3H2O or CsF gave highly enantioenriched 1-pyridyl-1-arylethanes in high er.
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ورودعنوان ژورنال:
- Chemical communications
دوره 50 31 شماره
صفحات -
تاریخ انتشار 2014