Tritioacetylating Reagents and Processes for Preparation Thereof

Patent Tritioacetylating Reagents and Processes for Preparation Thereof 

Saljoughian etal, US Patent 6,160,128 (December 12, 2000) Assignee The Regents of the University of California Utility Radiolabeled Acetylating Reagent 

N-Hydroxyphthalimide (8.7 mmol), iodoacetic acid (8.7 mmol) and 1,3-dicyclohexylcarbodiimide (8.7 mmol) were dissolved in 250ml EtOAc and stirred 5 hours at room temperature. The mixture was filtered, dried, the residue crystallized in ethanol, and the product isolated in 75% yield, mp = 120 °C. 

The product from Step 1 (0.05 mmol) was dissolved in 1 ml EtOAc, 10% palladium on carbon (10 mg) and 4 jl1 triethylamine added and the mixture hydrogenated under one atmosphere 10% tritium gas 2 hours. Thereafter, 1 ml methyl alcohol was added, the catalyst removed, the residue dissolved in 1 ml dg-THF, and the product isolated. The total radioactivity was assessed by liquid scintillation counting as 10 jLCi with a radioactivity yield of 7.2%. 

The preparation of N-deuterioacetoxyphthalimide, (1), is described below by the author in the current invention and elsewhere (2). 

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