2,2,2-trifluoro-N-[2-(3-fluorophenyl)ethyl]acetamide → HCID 178431087, Verbindung

Temperatur

50 °C

Following general procedure F using 4e (58.8 mg, 0.25 mmol), B2pin2 (127 mg, 0.50 mmol), [Ir(COD)OMe]2 (2.5 mg, 0.00375 mmol) and dtbpy (2.0 mg, 0.0075 mmol) in THF (1.25 mL). Stirred in vial at 50 °C for 20 hours. Analysis of crude 1 H NMR using internal standard 1,2‐dimethoxyethane showed 1.4:1 meta:para borylation in 89% yield (these numbers include the meta/para products which have also undergone NH borylation). The crude product was purified by silica gel chromatography (15% EtOAc in Petroleum Ether 40‐60 o C) which resulted in the cleavage of the N‐B bond and reprotonation of the NH‐borylation products and gave the title compound (as a 1.7:1 mixture of meta:para ratio, as determined by 1 H NMR) as a colourless oil (84 mg, 0.23 mmol, 93%). By subtracting the resonances for the meta isomer, the NMR data of the para isomer can be assigned as follows:

ORD-Eintrag

ord-708a1c59dc33408ebec4d803b94c9bdb

Quelldatensatz

Borylation dataset from Roche

DOI

10.1002/anie.201708967