METHOD OF PRODUCING CHEMICALLY ACTIVE PHOSPHOROUS ACID

摘要

FIELD: chemical technology, inorganic chemistry. SUBSTANCE: method is based on reaction of phosphorus trichloride with tert.-butanol in presence of catalytical amount of aluminium-fluoro-potassium-tris(phosphite) of the formula AlFK[OP(O)H(OH)](I) that is insoluble in water and organic solvents. Under reaction conditions compound I forms complex with intermediate and the end product and converts phosphorous acid to an active phosphorous acid (APA). Process is carried out by addition of phosphorus trichloride to I suspension in tert.-butanol at reaction mass boiling. APA is crystallized at the end of addition. Mixture is boiled for additional 10-30 min to terminate reaction and remained for night. Tret.-butanol is poured off, solid residue is kept under vacuum and APA is obtained at quantitative yield. APA esterification with 2-ethylhexanol to di-(2-ethylhexyl)phosphite in toluene continues 30 min at 100% yield as compared 16 h (yield is 56%) for usual phosphorous acid. APA is esterified with n-decanol at equimolar ratio of reagents under mild conditions (in benzene) and monodecylphosphite is obtained at quantitative yield. EFFECT: improved method of producing.