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Our ongoing search for underdeveloped functional group combinations has brought to light α-fluorinated aminoalkylboronic acids, a new class of molecules featuring the B-CF linkage. These compounds can now be generated from secondary amines and α-boryl aldehydes through electrophilic fluorination of boryl enamines or enamides. Fluorinated β-aminoalkylboronic acids show no signs of degradation under ambient conditions. We present evidence for the involvement of chair-like motifs, favored over the acyclic forms by up to 1.7±0.1 kcal mol -1 in water and held together by an amine-boronate hydrogen bond. Fluorinated β-aminoalkylboronic acids are stable over a wide pH range and are characterized by a pK a of 3.4, which is the lowest of any alkylboronic acid., (© 2021 Wiley-VCH GmbH.)

A series of thirty-three N,N'-diaryl, dialkyl, and alkyl-aryl ureas have been prepared in pyridine or toluene by reaction of silylamines with CO 2 . This protocol is shown to provide facile access to 13 C-labeled ureas, as well as chiral and macrocyclic ureas. These reactions proceed through initial generation of the corresponding silylcarbamates, which subsequently react with silylamine under thermal conditions to afford the thermodynamically favored urea and disilyl ether., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An enantioselective copper-catalyzed intramolecular borylacylation is reported. The reaction proceeds through an initial enantioselective borylcupration of the styrene, followed by a nucleophilic attack on the tethered carbamoyl chloride. The products, chiral borylated 3,3-disubstituted oxindoles, were generated in excellent yields and enantioselectivities. The versatile carbon-boron bond provides a platform for a wide array of diversification., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)