Synthesis of Fluorinated Aminoalkylboronic Acids from Amphoteric α‐Boryl Aldehydes

Abstract

Our ongoing search for underdeveloped functional group combinations has brought to light a-fluorinated aminoalkylboronic acids, a new class of molecules featuring the B-CF linkage. These compounds can now be generated from secondary amines and a-boryl aldehydes through electrophilic fluorination of boryl enamines or enamides. Fluorinated baminoalkylboronic 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 AE 0.1 kcal mol À1 in water and held together by an amine-boronate hydrogen bond. Fluorinated b-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.

Electrophilic Fluorination of Alkenes via Bora‐Wagner–Meerwein Rearrangement. Access to β‐Difluoroalkyl Boronates

“…[2] In a particularly interesting class of reagents the boron containing groups control the outcome of the fluorination reaction. [3] Here, we present an electrophilic fluorination reaction of vinyl boronate reagents proceeding via MIDA boronate [4] rearrangement.…”

Reactivities of α‐Oxo BMIDA Gold Carbenes Generated by Gold‐Catalyzed Oxidation of BMIDA‐Terminated Alkynes

“…While α-BMIDA aldehydes [15] were known as versatile building blocks in organic synthesis, the synthesis of α-BMIDA ketones was only reported once, [14] and their…”

Electrophilic Fluorination of Alkenes via Bora‐Wagner–Meerwein Rearrangement. Access to β‐Difluoroalkyl Boronates

“…[2] In a particularly interesting class of reagents the boron containing groups control the outcome of the fluorination reaction. [3] Here, we present an electrophilic fluorination reaction of vinyl boronate reagents proceeding via MIDA boronate [4] rearrangement.…”