p-Toluenesulfonic acid → HCID 54757414, compound

Participants

Reaction Conditions

Reaction Steps

To (3,3-diethoxypropyl)amine (1.00 equiv) in THF (2 volumes) was charged di-t-butyldicarbonate (1.05 equiv) in THF (3 volumes). The reaction was heated to 45° C. and held for ½ h. Analysis showed the disappearance of starting material, and the resulting solution was heated to 65° C. p-Toluene sulphonic acid (0.1 equiv) and water (5 volumes) were charged over 10 mins, heating continued at 65° C. and held for ½ hour. Analysis showed disappearance of tert-butyl (3,3-diethoxypropyl)carbamate. Toluene (15 volumes) charged, layers separated and washed with water (5 volumes). A fraction of the solution obtained (0.95 equivs) was charged to a solution containing 6-(1-amino-2-methyl-propyl)-5-benzyl-3-methyl-5H-isothiazolo[5,4-d]pyrimidin-4-one (method 30) (1 equiv), toluene (5 volumes) and molecular sieves (1 weight equivalent). The reaction mixture was stirred overnight at room temperature until the reaction was complete. THF (2.5 volumes) were charged followed by sodium acetoxyborohydride (2.0 equiv) and the resulting mixture held overnight until reaction was complete. Aqueous acetic acid (20% v/v, 2.5 volumes) were charged over 10 minutes, stirred at room temperature for 10 minutes, filtered and washed with water (2.5 volumes). The layers were separated and the organic layer was concentrated under vacuo at 50° C. Further toluene was charged (2.5 volumes) and the solvent removed. The product was obtained as an orange oil (typical yield 92%). m/z 486 (MH+).

Provenance & Evidence