反应详情

1 ml of an approximately 2 molar solution of butyllithium in hexane is added over a period of 15 minutes to a solution, cooled to -10° C., of 282 mg (2 mmols) of isocyanoacetic acid tert.-butyl ester in 3 ml of dry hexane (distilled over sodium), whilst stirring vigorously and in a nitrogen atmosphere. The suspension which forms is stirred for a further 10 minutes and a solution of 413 μl (2 mmols) of diethyl phosphorochloridate in 5 ml of dry hexane is then added over a period of 15 minutes. The reaction mixture is stirred for a further 30 minutes, then treated with 20 ml of benzene and 5 ml of water and stirred vigorously for a further 10 minutes. The organic phase is washed with 3 times 5 ml of saturated aqueous sodium chloride solution, dried over sodium sulphate and evaporated in vacuo. The residue is chromatographed on silica gel. Benzene/ethyl acetate, 3:1, elutes diethylphosphono-isocyanoacetic acid tert.-butyl ester as a pale yellow oil; IR spectrum (in methylene chloride): characteristic bands at 3.4; 4.64; 5.70; 7.30; 8.00; 8.70 and 9.80μ.

1. stirringThe suspension which forms is stirred for a further 10 minutes
2. stirringThe reaction mixture is stirred for a further 30 minutes
3. stirringstirred vigorously for a further 10 minutes
4. washThe organic phase is washed with 3 times 5 ml of saturated aqueous sodium chloride solution
5. dry with materialdried over sodium sulphate
6. customevaporated in vacuo
7. customThe residue is chromatographed on silica gel