Borylcopper reagents

Borylcopper reagent, coupling reactions, 9, 171 Borylcopper(I) reagents, in addition reactions, 9, 166 Boryl ligands... 

Subsequently, borylcopper reagents were also synthesized, as shown below. As softer nucleophiles than boryllithiums, borylcopper reagents exhibit significantly different reactivity, undergoing, for instance, conjugate additions with a, -unsaturated carbonyl compounds ... 

The synthesis of a borylcopper(i) reagent from bis(pinacolato)diboron (B2pin2) and GuOAc was developed. The reagent used for the 1,4-addition to a,/3-unsaturated ketone 146230 led to an intermediate for the total synthesis of cylindricine C and 2-epicyclindricine G (Equation (52)).231... 

A method for in situ preparation of a borylcopper species from diboron and CuOAc was recently developed.200,201 The reagent coupled with allyl acetate to give allyl boronates 185 (Equation (63)).334... 

Pinacolatoboration. Hydroboration of 1-alkynes to give 2-pinacolato-l-alkenes is effected with bis(pinacolato)diboron in the presence of CuCl and KOAc. Perhaps a borylcopper species is involved in the reaction. The same reagent is useful as a nucelophile toward allylic halides and Michael acceptors. 

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