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In the presence of Pd(PPh3)4, NaBr and KF·2H2O the cross-coupling reaction of heteroaryl triflates with trans-cyclopropylboronic acids proceeds readily to give pure trans-cyclopropyl heteroarenes in moderate to good yields. The X-ray crystallography of compound 3g and 1H-NMR spectra of all products show that the configuration of the cyclopropyl group was retained during the reaction. Under the same reaction conditions, highly optically active cyclopropyl-substituted heteroarenes (up to 94% ee) were obtained by cross-coupling of heteroary/triflates with enantiomerically enriched cyclopropylboronic acids.

The palladium-catalyzed cross-coupling reaction of cyclopropylboronic acids with acyl chlorides was achieved by the combination of Ag2O and K2CO3 as the base. Highly enantiomerically enriched cyclopropyl ketones (ee >90%) were also obtained by the reaction of corresponding chiral cyclopropylboronic acids.

The reaction of allylcarbonate with lithium trialkylalkynylborates catalysed by Pd(PPh 3 ) 4 , affords 1,4-alkadienes in good yields and high stereoselectivity.

Chloromagnesium trialkylvinylborate, (R3BCHCH2)MgCl, on reaction with carbon dioxide under pressure, followed by oxidation with alkaline hydrogen peroxide, gives a β-hydroxycarboxylic acid.