Concept

Composé organophosphoré

Publications associées (48)

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About the structure of phosphorus ylides: electron distribution and geometry

Using 13C-chem. shifts as a probe for the electronic environment of carbon centers, triphenylphosphoniomethanide, the model case of a reactive phosphorus ylide, have much more zwitterion than PC double bond character. Triphenylphosphoniopropenide (tripheny ...

1990

Phosphorus ylides

A review with 252 refs. [on SciFinder (R)] ...

Academic Press1978

Stereochemistry of olefination by phosphorus ylides

A review, with 6 refs., of the prepn. of olefins from phosphonium ylides and carbonyl compds. and from phosphonium ylides, carbonyl compds., org. Li compds., and reactive halogen compds., such as MeCOCH2Cl and EtI. [on SciFinder (R)] ...

1970

Stereoisomer-uniform olefins

Homogeneous stereoisomeric olefins of the general formula I (R1 and R2 = alkyl, R3 = H and(or) alkyl) were prepd. by reacting a phosphorus ylide (general formula Ar3P+:C-HR) and a carbonyl compd. R2COR3 with stoichiometric amt. of a strong base, followed b ...

(Badische Anilin- & Soda-Fabrik AG).1968

Olefination with phosphorus ylides. I. Mechanism and stereochemistry of the Wittig reaction

Unstabilized P ylides and their betaines added Li salts, losing most of their reactivity, and were reactivated with tert-BuOK, making thus possible the retardation or the acceleration of the Wittig reaction. The C:O olefination often yielded an isomer mixt ...

1967

Eine Methode zur Darstellung selektiv deuterierter Verbindungen

H atoms in the a-position to a quadricovalent P atom could be exchanged by D with D2O under mild alk. conditions. The phosphonium salts, which can be readily deuterated under these conditions, served as the key intermediates for the synthesis of selectivel ...

1964

Rearrangement and degradation of alpha-heterofunctional substituted phosphonium salts

cf. CA 55, 23400c; Hellmann and Bader, CA 56, 11615h. Treatment of phosphonium salts of the type (Ph3PCH2X)OH(I, X = SMe; II, X = Cl; III, X = Br) with N aq. NaOH gave Ph3PO and MeX. With II and III a Ph group migrated to give Ph2(PhCH2)PO (17% from II, 33 ...

1962

Die Zersetzung von Diazoverbindungen in Gegenwart von Triphenylphosphin

cf. CA 55, 23400c. The Cu salt decompn. of diazo compds. in the presence of Ph3P opens up a new path to the synthesis of phosphorus-ylides. Ph3P (10 millimoles) and 10 millimoles 0.6M CH2N2 in Et2O treated 15 min. with 1 millimole anhyd. CuCl in 70 ml. tet ...

1962