A catalyst composed of an organic phosphorus compound having a trivalent or pentavalent phosphorus atom and at least one carbon-phosphorus bonding or a combination of the organic phosphorus compound and a halogen atom-containing compound is effective for decarbonylation, that is, for releasing carbon monoxide from a compound containing a moiety of -CO-CO-O- in its molecular structure.
averaged 1JPCipso(aryl) coupling constant was used to elucidate the characteristic structural properties of Wittig and thio Wittig intermediates derived by treatment of the series Ph3PCH2 (2a), Ph2MePCH2 (2b), and PhMe2PCH2 (2c) with bis(p-methoxyphenyl) ketone to give 3 or benzophenone (to give 3′) or bis(p-methoxyphenyl) thioketone (to give 5), respectively. The oxaphosphetane series 3′a–3′c shows a strong
Unprecedented CP systems: Me3SiX (X=Br, I) catalyses rearrangements of PIII esters R′R′′POR into the corresponding phosphoryl systems, providing a simple, mild and efficient route to a variety of structures containing PC bonds. The mechanism has been found to be fundamentally different from that of the Arbuzov–Michaelis reaction and includes three definite steps a, b and c (see scheme).
Process for hydroxylating olefins in the presence of an osmium containing catalyst and organic halogenated hydrocarbon co-catalyst
申请人:EXXON RESEARCH AND ENGINEERING COMPANY
公开号:EP0101167A1
公开(公告)日:1984-02-22
A process for hydroxylating olefins with an organic hydroperoxide and water in the presence of an osmium containing catalyst (e.g. OsO4) and an organic halogenated hydrocarbon co-catalyst (e.g., n-butyl iodide) is disclosed.
An improved process for preparing a diaryl carbonate from a diaryl oxalate in a liquid phase by decarbonylation utilizes a reaction vessel composed of two or more reaction chambers which are connected in series. The process is composed of the steps of continuously introducing the diaryl oxalate and an organic phosphorus compound having a trivalent or pentavalent phosphorus atom and at least one carbon-phosphorus bonding into the first chamber and continuously recovering a reaction mixture mainly containing the diaryl carbonate from the last chamber under the condition that a mixture of the diaryl oxalate and the organic phosphorus compound is heated in the reaction chambers, while discharging carbon monoxide released from the mixture.