4-chloro-2-hydroxy-6-methoxybenzaldehyde synthesis

Yield:1427396-66-4 99%

Reaction Conditions:

with boron tribromide

Steps:

37.B 37B.

37B.
4-Chloro-2-hydroxy-6-methoxybenzaldehyde
A stirred solution of 4-chloro-2,6-dimethoxybenzaldehyde (Example 37A, 1.95 g, 9.72 mmol) in DCM (20 mL, 311 mmol) at -78° C. was slowly added boron tribromide (9.72 mL, 9.72 mmol).
The reaction mixture was stirred at -78° C. for 10 minutes then warmed to r.t. and stirred for 1 hour while monitoring reaction progress by LCMS.
Once all s.m. had been consumed, the reaction was quenched with water and extracted with DCM.
The organic phase was washed with brine, dried (MgSO₄), filtered and concentrated to dryness to give the title material (1.79 g, 9.59 mmol, 99% yield) as a purple solid. LC (Method B): 2.199 min. LCMS (APCI) calcd for C₈H₈ClO₃ [M+H]⁺ m/z 187.02. found 187.0. ¹H NMR (CDCl₃, 400 MHz) δ ppm: 11.89 (s, 1H), 10.20 (s, 1H), 6.75 (t, J=2.0 Hz, 1H), 6.66 (m, 1H), 3.91 (s, 1H).

References:

US2013/289238,2013,A1 Location in patent:Page/Page column