The Preparation of Desflurane by the Vapor-Phase Fluorination of Isoflurane

Abstract

There are several known processes for manufacturing the commercially important anaesthetic desflurane (CF 3 CHFOCHF 2 ) by the catalyzed reaction of commercially available isoflurane (CF 3 CHClOCHF 2 ) with hydrogen fluoride. The present available methods have the disadvantage of high catalyst usage, with consequent environmental problems, or of having to trade off low conversion against low selectivity. An alternative catalyst system was therefore sought that would avoid these problems, but would still give the benefits of a vapor-phase process and, in particular, a long catalyst life. A catalyst consisting of antimony pentafluoride supported on activated carbon has now been found to provide the basis for a novel vapor-phase process for the fluorination of isoflurane to desflurane using hydrogen fluoride. The process operates with a long catalyst life, high conversion, and high selectivity.

A new insight of degradation reaction mechanism on desflurane radical with a catalyst of NO: A theoretical perspective

“…This process is predicted to be an oxygen molecule addition reaction into CF 3 leading to a possible complex CF 3 Table 3, the calculated apparent rate constant is 6.88×10 11 cm 3 ·molecule -1 ·s -1 , implying that the reaction is very fast and feasible easily. And this oxidation reaction is easy to occur in room temperature condition.…”

“…Desflurane (named as 1,2,2,2-tetrafluoroethyl difluoromethyl ether, CF 3 CHFOCHF 2 ), a highly volatile narcotic gas, has been the concerns of several investigations [3][4][5][6][7]. In the recent reports, many studies have been carried out for exploring the chemical properties and conformational problems of desflurane both in the experiments [3,5,6] and computational investigations [4,7].…”

“…In the recent reports, many studies have been carried out for exploring the chemical properties and conformational problems of desflurane both in the experiments [3,5,6] and computational investigations [4,7]. Sivaramakrishnan et al [3] reported a method for manufacturing the commercially important anaesthetic desflurane (CF 3 CHFOCHF 2 ) by the catalyzed reaction of commercially available isoflurane (CF 3 CHClOCHF 2 ) with hydrogen fluoride, which has the advantage of a long catalyst life, high conversion and high selectivity.…”

“…In the recent reports, many studies have been carried out for exploring the chemical properties and conformational problems of desflurane both in the experiments [3,5,6] and computational investigations [4,7]. Sivaramakrishnan et al [3] reported a method for manufacturing the commercially important anaesthetic desflurane (CF 3 CHFOCHF 2 ) by the catalyzed reaction of commercially available isoflurane (CF 3 CHClOCHF 2 ) with hydrogen fluoride, which has the advantage of a long catalyst life, high conversion and high selectivity. Sutradhar et al [4] investigated the conformation property, acidity/basicity property and the interaction with one water molecule of desflurane (CF 3 CHFOCHF 2 ) using ab initio MP2/aug-cc-pvDZ and density functional theory B3LYP/6-311++G** methods, in which, they discussed the binding energies with water and analyzed the natural bond orbital in detail.…”

“…Although some experiments [3][4][5][6] have exposed some important corresponding information on the mother molecule desflurane, many uncertainties still remain in our knowledge of the atmospheric lifetimes and atmospheric fate of the common inhaled anesthetics. The desflurane radical (CF 3 CFOCHF 2 , named as DES) is the main product of desflurane H abstraction reaction [6,7], which is about 20 times faster than another desflurane radical (CF 3 CHFOCF 2 ) producing.…”