4,4,5,5-Tetramethyl-2-(2-methyl-3-nitrophenyl)-1,3,2-dioxaborolane → 2-Methyl-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)aniline

Beteiligte Stoffe

Reaktionsschritte

A 500-mL round-bottomed flask equipped with a magnetic stirrer was charged with 4,4,5,5-Tetramethyl-2-(2-methyl-3-nitro-phenyl)-[1,3,2]dioxaborolane (3) (8.44 g; 32.1 mmol) and methanol (150 mL). The reaction flask was twice evacuated and back-filled with argon. 10% Palladium on charcoal (50% wet, 425 mg dry weight) was then added to the solution, and the reaction flask evacuated and back-filled with hydrogen three times. The reaction was then stirred under balloon pressure of hydrogen at room temperature for 13 h. After this time, the flask was twice evacuated and back-filled with argon, then filtered through a pad of Celite 521 and the filtrate concentrated in vacuo. The resulting residue was dried under high vacuum for 1 d to afford a quantitative yield (8.16 g) of 2-methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenylamine (4) as a white solid: mp 110-112° C.; MS (ESI+) m/z 234 (M+H).

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