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Carbon-phosphorus-oxygen rings

Treatment of (5,5)-/ /.v(2-hydroxypropyl)phcnylphosphine oxide with initially base followed by Cl(CH2)20(CH2)20Tf gave the dichloride intermediate, which with base and either catechol or tosyl amine in DMF and elevated (150 °C) temperatures generated the macrocyclic phosphane oxide 35 in 15% yield or the l-phospha-10-aza-18-crown-6-ether in 44% yield 06EJOC154 . [Pg.475]

CARBON-PHOSPHORUS-OXYGEN (AND SULFUR) -METAL RINGS... [Pg.387]

The oxazoliumcarboxylic acid (147) is easily decarboxylated via the ylide (148) the neutral compound (149) is much more stable due to the low equilibrium concentration of the zwitterionic tautomer (150 Scheme 7). Oxazolium salts lacking substituents at the 2-position react with dialkyl acylphosphonates in the presence of triethylamine to give mixtures of l,4-oxazin-3-ones and 2-azetidinones the reaction (see Scheme 8) proceeds by electrophilic attack of the phosphonate on an oxazolium ylide, e.g. (151), followed by insertion of oxygen into the carbon-phosphorus bond, ring-opening, and formation of the enolate anion (152) which can cyclize in two alternative ways with expulsion of the phosphonate group. [Pg.194]

Phosphorus—phosphorus bonds, addition, to alkynes, 10, 751 Phosphorus rings, chromium carbonyl link arsenic rings, 5, 226 As, Sb, Se, Te, Sn rings, 5, 226 boron rings, 5, 222 carbon rings, 5, 224 characteristics, 5, 221 oxygen rings, 5, 227... [Pg.170]

RINGS AND CAGES WITH PHOSPHORUS, CARBON AND OXYGEN [1,116-124]... [Pg.473]

Among the possible ring systems based on phosphorus, oxygen and carbon, the dioxaphosphinanes (dioxaphosphorinanes), dioxaphospholanes and dioxaphospholes have been most studied (Table 6.25). [Pg.473]

See other pages where Carbon-phosphorus-oxygen rings is mentioned: [Pg.475]    [Pg.475]    [Pg.475]    [Pg.475]    [Pg.340]    [Pg.479]    [Pg.328]    [Pg.329]    [Pg.471]    [Pg.479]    [Pg.310]    [Pg.443]    [Pg.323]    [Pg.325]    [Pg.364]    [Pg.97]    [Pg.1497]    [Pg.77]    [Pg.145]    [Pg.145]    [Pg.147]    [Pg.218]    [Pg.56]    [Pg.335]    [Pg.335]    [Pg.263]    [Pg.573]    [Pg.593]    [Pg.214]    [Pg.429]    [Pg.573]    [Pg.95]    [Pg.144]    [Pg.55]    [Pg.345]    [Pg.830]    [Pg.363]    [Pg.214]    [Pg.164]    [Pg.351]   


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Carbon oxygenated

Carbon oxygenation

Carbon-phosphorus

OXYGEN phosphorus

Oxygen ring

Phosphorus rings

Phosphorus-oxygen rings

Ring Carbon

Ring oxygenation

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