Dimethyl Sulfoxide → 6-Chloro-4-(isopropylamino)nicotinaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of DMSO (13.43 mmol, 3.5 equiv.) in dry DCM (30 mL), oxalyl chloride (11.51 mmol, 3 equiv.) was added at −78° C. After being stirred for 20 min, (6-chloro-4-(isopropylamino)pyridin-3-yl)methanol (75) (770 mg, 3.84 mmol) was added to the above reaction mixture at −78° C. and stirred for 2 h. The reaction mixture was allowed to warm up to −20° C. and added Et3N (19.19 mmol, 5 equiv.) dropwise over a period of 5 mins. The reaction mixture was allowed to warm up to 0° C. over 30 mins and quenched with ice-flakes followed by 10% NaHCO3 solution. The organic layer was separated, aqueous layer was extracted with DCM (twice). The organic layers were collected together, dried over Na2SO4, filtered and concentrated to give crude aldehyde. The crude material obtained was purified by column chromatography through silica gel and EtOAc: pet ether as eluent provided the desired compound, 6-chloro-4-(isopropylamino)nicotinaldehyde. LC/MS: Acquity BEH C18 2.1×50 mm, 1.8 micron; Solvent A=0.1% TFA in water; Solvent B=0.1% TFA in ACN; gradient 0-100% B over 2 min; retention time: 0.76 min; LCMS (ES-API), m/z 199.26 (M+H).

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