HCID 1517066, compound → HCID 178431059, compound

Temperature

50 °C

Following general procedure F using 4h (62.9 mg, 0.25 mmol), B2pin2 (127 mg, 0.50 mmol), [Ir(COD)OMe]2 (2.5 mg, 0.00375 mmol) and 1a (3.8 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 7.7:0.43:1 meta:dimeta:para borylation (overall meta:para borylation 8.1:1) in 95% yield (these numbers include a small amount of the meta isomer that had 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 in the small amount of the NH‐borylation products and gave the title compound (as a 6.9:0.4:1 mixture of meta:dimeta:para ratio and overall meta:para ratio of 7.3:1, as determined by 1 H NMR) as a colourless oil (96 mg). A small amount of B2Pin2 impurity was found to be inseparable from the final product on silica. Corrected yield ‐ 88 mg, 0.24 mmol, 94%).

ORD record

ord-06b746e7690d4443a3d79c4bf96b7c92

Source dataset

Borylation dataset from Roche

DOI

10.1002/anie.201708967