N-Methyl-4,5,6,7-tetrahydro-1,3-benzothiazol-2-amine synthesis

Yield:40534-18-7 43%

Reaction Conditions:

with magnesium sulfate in acetone; for 1.25 h;Reflux;

Steps:

1

To a suspension of methylthiourea (XXXVIII) (10.0 g, 111 mmol), MgS0₄ (6.7 g, 55 mmol) in acetone (10 mL) at reflux was added a solution of 2- chlorocyclohexanone (XXXIX) (10.2 g, 111 mmol) and acetone (10 mL) over 15 min. The reaction mixture was heated at reflux for 1 h, and the reaction mixture was cooled to rt. The solution was poured into brine (80 mL), and basified with a solution of concentrated NH₄OH. EtOAc (200 mL) was added and layers were partition and separated. The organic phase was dried over Na2S0₄, filtered and concentrated under reduced pressure. The resulting crude residue was purified by column chromatography (EtOAc: hexanes, gradient elution) to afford 8.0 g (43%) of N- methyl-4,5,6,7-tetrahydrobenzo[d]thiazol-2-amine (XL). ESIMS found for (1739) C8H12N2S: mz 169.2 (M+l).

References:

WO2019/213295,2019,A1 Location in patent:Paragraph 007; 008