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Phosphorus oxochloride

Chlorination of 2-(pyrrol-l-yl)pyrrole 330 with sulfuryl dichloride gave the natural 2,3,4-trichloro-l-methyl-5-(perchloropyrrol-l-yl)pyrrole (Ql) 331 in 16% yield (Scheme 74) <2002AGE1740>. Treatment of l-(pyrrol-2-yl)dihy-dropyrrole-2,5-dione 329 with PCls at 55°C gave l-(l-methyl-3,4,5-trichloropyrrol-2-yl)dihydropyrrole-2,5-dione 332. Treatment of compound 329 with a mixture of phosphorus pentachloride and phosphorus oxochloride at 100 °C provided Ql in a yield of 7%. [Pg.97]

Two classical methods based on methylamines 58a have been developed for preparation of substituted methyl isocyanides-the second component of the reaction shown in Scheme 4.28. The first method consists of one stage, namely, treatment of amines with chloroform in the presence of alkalis the second method consists of two stages. The reaction with ethyl formate leads to formamides 58b, which are then dehydrated by treating with phosphorus oxochloride in the presence of tri-ethylamine (Scheme 4.29) (Jacobsen et al. 1996a). [Pg.226]

About 80-90% of the elemental P produced is reoxidized to (pure) phosphoric acid (p. 521). The rest is used to make phosphorus oxides (p. 503). sulfides (p. 506), phosphorus chlorides and oxochloride (p. 4%). and organic P compounds. A small amount is convened to red phos rftorus (see below) for use in the striking surface of matches for pyrotechnics and as a flame retarding agent (in polyamides). Bulk price for P4 is S2.00/kg. [Pg.480]

Hydroxyethylamino)quinoxalines 112a-e are cyclized into l,2-dihydroimidazo[l,2-a]quinoxalines 113a-e under the action of dehydrating agents, such as thionyl chloride, HCI or phosphorus(V) oxochloride (Scheme 4.52) (Hirotaka et al. 1970 Ohmori et al. 1997 Borchardt et al. 2010, 2011b). [Pg.240]

One of the key methods of synthesis of imidazo[l,2-a]quinoxalines on the basis of imidazoles is Ali-type synthesis. In this case, imidazole ring annulation is a result of formation of the C(3a)-C(4) bond. In particular, l-(2-acylaminophenyl)- or 1-(2-amino-carbonylaminophenyl)imidazoles 143, obtained by the reaction of N-(2-aminophenyl)imidazole 86c and acetyl chlorides or isocyanates, are converted under the action of phosphorus(V) oxochloride into 4-substituted imidazoquinox-alines 144 (Warner and Luber 1979a, b, c, 1980a, b, c, d, e Lamberth 1999 Chen et al. 2002b). More than 100 imidazo[l,2-ti]quinoxalines have been synthesized by this method (Scheme 4.65). [Pg.248]


See other pages where Phosphorus oxochloride is mentioned: [Pg.230]   
See also in sourсe #XX -- [ Pg.505 ]




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