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ChemicalBook CAS DataBase List 1,3-DI-BOC-2-METHYLISOTHIOUREA
107819-90-9

1,3-DI-BOC-2-METHYLISOTHIOUREA synthesis

2synthesis methods
-

Yield:107819-90-9 42 g (62%)

Reaction Conditions:

with sodium hydroxide;citric acid in water;tert-butyl alcohol;

Steps:

E E)

E) Preparation of N,N'-di-Boc-S-methylisothiourea To a stirring solution of di-t-butyl dicarbonate (100 g, 458 mmol) in t-butanol (300 mL) was added a solution of bis-S-methylisothiourea sulfate (32.7 g, 117 mmol) in water (150 mL), followed by a solution of sodium hydroxide (19.2 g, 480 mmol) in water (150 mL). After stirring for 48 hours, the mixture was concentrated to approximately one-third of the original volume in vacuo and diluted with diethyl ether (500 mL). The organic phase was washed once with water (250 mL), three times with 1 N citric acid (250 mL) and once again with water (250 mL). The organic phase was then dried (MgSO4), filtered and concentrated in vacuo to give 42 g (62%) of a white solid.

References:

US5914319,1999,A

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