Carbethoxymethylene triphenylphosphorane

Ethyl (triphenylphosphoranylidene)acetate is available from FIuka AG and Trldom Chemical Inc. under the name (ethoxycarbonylmethylene)triphenyl-phosphorane and from Aldrich Chemical Company, Inc. under the name (carbethoxymethylene)triphenylphosphorane. The reagent may be prepared from triphenyl phosphine and ethyl bromoacetate by the following procedure. ... 

Carbethoxymethylene)triphenylphosphorane, (Ethoxycarbonylmethylene)tri-phenylphosphorane Acetic acid, (triphenylphosphoranylidene)-, ethyl ester (8,9) (1099-45-2)... 

Figure 2.7 shows the procedure of synthesizing l,4-dimethylcubane-6 s-acrylate [3]. Crude dialdehyde (530 mg, 3.28 mmol) was dissolved in anhydrous benzene (20 ml). (Carbethoxymethylene)triphenylphosphorane (2.86 g. 

The pyrido[2,3- pyrimidinones 380 and 381 were thermally obtained from boiling the ethyl acrylate derivatives 378 and 379, respectively, with l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and EtNHPd in THF (Scheme 13) <2001W02001055148, 2004USP2004009993>. The acrylates were obtained from reaction of the corresponding pyrimidine-5-carbaldehyde with (carbethoxymethylene)triphenylphosphorane. On the other hand, acrylate 382 was converted into 383 via aza-Wittig cyclization (Equation 32) <1997LA1619>. 

Solid state Wittig-Horner reaction of 4-methyl- (43a), 4-ethyl- (43b) and 3,5-di-methylcyclohexanone (44) as their inclusion complex with optically active host compound and (carbethoxymethylene)triphenylphosphorane (45) gave optically active 4-methyl- (46a), 4-ethyl- (46b) and 3,5-dimethyl-l-(carbethoxymelhy-lene)cyclohexane (47), respectively [16]. For example, when a mixture of the finely powdered 1 1 inclusion complex of 43a with 2b (1.5 g) and 45 (2.59 g) was kept at 70 C, the Wittig-Horner reaction was completed within 4 h. To the reaction mixture was added ether-petroleum (1 1) and the precipitated solid (Ph PO... 

The acetylenic aldehyde (3.4 g, 10.0 mmol) was dissolved in toluene (200 mL). (Carbethoxymethylene)triphenylphosphorane (18.1 g, 50.0 imnol) was added in 1 portion. The stirred mixture was warmed to 100 °C and kept at this temperature for 12 h. The homogeneous solution was cooled to room temperature and washed sequentially with water (50 mL) and brine (50 mL). The organic phase was dried over sodium sulfate, hltered, concentrated, and the crude mixture purihed by chromatography (silica gel, hexanes EtOAc, 98 2) to afford 4.2 g (99%, E Z > 9 1) of the -olehn. 

Wittig olefinations continue to be exploited for the synthesis of heterocyclic species. For example, acylphosphoranes (65), formed as intermediates in the condensation of (trimethylsilyl)methylenetriphenylphosphorane and the silyl esters of 0-acyl(aroyl)salicylic acids, undergo intramolecular Wittig reactions producing substituted chromenones (66) (Scheme 14). " Treatment of diox-olanones (67) with (carbethoxymethylene)triphenylphosphorane produces the corresponding a,p-unsaturated esters (68), which are useful precursors to... 

The well known Wittig reaction has been reported to occur in solid phase. In this procedure a 1 1 mixture of the finely powdered inclusion compound of cyclohexanone or 4-methyl cyclohexanone and (-)-B (derived from tartaric acid s and a catalytic amount of benzyltrimethyl ammonium hydroxide) was heated at 70 °C with Wittig reagent carbethoxymethylene triphenylphosphorane to give optically active 1-(carbethoxymethylene) cyclohexane (Scheme 17) or... 

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