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Patent Watch--February 9, 2009

The following record is from the CAplus^SM database

CAPLUS COPYRIGHT 2009 ACS

PATENT NUMBER:	EP 1870398
TITLE:	One-step catalytic process for the synthesis of isocyanates
INVENTOR(S):	Serrano Fernandez, Francisco Luis; Almena Munoz, Beatriz; Padilla Polo, Ana; Orejon Alvarez, Arancha; Claver Cabrero, Carmen; Castillon Miranda, Sergio; Salagre Carnero, Pilar; Aghmiz, Ali
PATENT ASSIGNEE(S):	Repsol-Ypf,S.A., Spain
SOURCE:	U.S. Pat. Appl. Publ., 10pp. CODEN: USXXCO
LANGUAGE:	English

ABSTRACT: A one-pot process for the synthesis of isocyanates, polyisocyanates or mixts. thereof includes the steps of : (i) prepg. a mixt. comprising an amine, an alc., an oxygen-contg. gas, carbon monoxide, a metal complex catalyst selected from the group consisting of macrocyclic complex catalysts and cobalt Schiff base catalysts; and a solvent selected from the group consisting of aliph. or arom. halocarbons, perhalogenated alcs., halogenated ethers, halogenated ketones, perfluorinated hydrocarbons, polymers of chlorotrifluoroethylene having the formula -(CF2-CFCl)n wherein n is between 2 and 10, and mixts. thereof; (ii) subjecting the resulting mixt. to a first heating under pressure; (iii) cooling and depressurizing the mixt. resulting from the previous step; and (iv) subjecting the mixt. of the previous step to a second heating to sep. out the isocyanate product from the mixt. Thus, aniline 15.5 g, N,N'-(bis(3,5-di-tert-butylsalicylidene)ethylenediamino)cobalt(II)/silica catalyst 7.6 g, NaI 1.78 g, and 2,2,2-trifluoroethanol (TFE) 488 g were introduced to an autoclave; the autoclave was pressurized with carbon monoxide and oxygen in a volumetric ratio of 19/1; the temp. was increased to 120.degree.C, and the total pressure was maintained const. at 40 bars; the reaction mixt. was stirred for 3 h; the reactor was then cooled to room temp., depressurized, and 1,2-dichlorobenzene (DCB) 97.8 g was charged in the reactor; the temp. was increased to 180.degree.C under atm. pressure; the vapors of TFE were sepd. and condensed for reuse; in the bottom of the reactor, a mixt. of DCB and phenylisocyanate was obtained; from this mixt., phenylisocyanate was obtained (by distn.) in 51.3% yield with 99% wt./wt. purity.