Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Oxygen flash vacuum pyrolysis

The behaviour of 16 substituted benzoyl/arylcarbamoyl and benzoyl/arylthiocar-bamoyl stabilized ylides under conditions of flash vacuum pyrolysis has been investigated.15 Kinetic studies show the thiocarbamoyl ylides to react consistently faster than their carbamoyl analogues and substituent effects suggest a polar cyclic transition state, which involves attack by the benzoyl oxygen on the carbamoyl/thiocarbamoyl NH (Scheme 5). [Pg.280]

The only example of the 1,4,5-benzoxathiazepine system (173) has been obtained from 2-(aryloxy) ethanesulfonyl azides (171) either by thermal decomposition in oxygen-free Freon 113 or by flash vacuum pyrolysis via the adducts (172) derived from the initially formed ethanesulfonylnitrenes (Scheme 27) <84JOC3ll4>. [Pg.352]

Flash vacuum pyrolysis (625 °C 0.1—1 Torr) of 2,3-benzoxazin-l-one (328) produces biphenylene (7%) and 2-phenyl-3,l-benzoxazin-4-one (320 R = Ph) (11%) rather than the hoped-for benzazete-derived products. The azirino-a-lactone (329) has been suggested as a possible reaction intermediate. The gas-phase thermal and photochemical decompositions of nitrogen, oxygen, and sulphur heterocycles have been reviewed. [Pg.209]

See other pages where Oxygen flash vacuum pyrolysis is mentioned: [Pg.71]    [Pg.62]    [Pg.671]    [Pg.198]    [Pg.198]    [Pg.965]    [Pg.1139]    [Pg.7]    [Pg.936]    [Pg.965]    [Pg.292]    [Pg.188]    [Pg.538]    [Pg.90]    [Pg.2368]    [Pg.278]    [Pg.161]    [Pg.194]    [Pg.61]    [Pg.310]    [Pg.188]    [Pg.31]    [Pg.276]    [Pg.186]    [Pg.71]    [Pg.262]   
See also in sourсe #XX -- [ Pg.229 , Pg.230 ]



SEARCH



Flash pyrolysis

Flash vacuum pyrolysi

Flash vacuum pyrolysis

Pyrolysis vacuum

Vacuum flashing

© 2024 chempedia.info