| 摘要 |
1473457 Dioldiones SNAMPROGETTI SpA 12 June 1975 [12 June 1974J 25279/75 Heading C2C Compounds of formula where R<SP>1</SP>, R<SP>2</SP>, R<SP>3</SP> and R<SP>4</SP> are H or hydrocarbyl are prepared by oxidizing with an oxidizing system comprising osmium tetroxide and an alkali or alkaline earth metal chlorate. Water or an organic solvent may be used. Osmium tetroxide may be recovered by flushing with an inert gas and trapping in a quantity of starting material or by solvent extraction followed by addition of starting material to the extract and evaporation of the solvent, examples prepare: 2,5-dihydroxyhexane- 3,4 - dione, 2,5 - dihydrbxyheptan - 3,4 - dione and 1,4-dihydroxypentan-2,3-dione. Reference has been directed by the Comptroller to Specification 1,212,090. |
