Triethyl phosphonoacetate, reaction with

Triethyl phosphonoacetate, reaction of sodium derivative with cyclohexanone to yield ethyl cvclo hexy lideneacetate, 46, 45 1 nfluoroacetic anhydride, 46, 98 p,0 0 Trifluorostyrene, 47, 52 Trusopropvl phosphite as reagent in dechlorination of decachlorobi 2,4 cyclopentadienyl, 46, 93 1,3,5-Tnketones, from aroylationof 1,3-diketones, 46, 59 from 4-pyrones, 46, 59 Tnmethylamine oxide, reaction with x-octyl iodide to yield octanal, 47, 96... 

Triethyl phosphonoacetate, reaction of sodium derivative with cyclohexanone to yield ethyl cyclo-hexylideneacetate, 45, 4S Trifluoroacetic anhydride, 45, 98 a,a,a-Trifluoroacetophenone, reaction with triphenylphosphine and sodium chlorodifluoracetate, 48,116 m-Trifluoromethylaniline, methylation of with trimethylphosphate, 49, 111... 

Wittig-Horner reaction a,p-unsaturated esters. The reaction of triethyl phosphonoacetate (1) with aldehydes can be carried out in water using potassium carbonate at 20° or potassium hydrogen carbonate at 100°. 

Barium hydroxide [33, 34] is a strong base which has been employed not only in organic synthesis but also for other purposes. The commercially available octahydrate, l a(OI 1)2 8 11,/) is often used after transformation to the anhydrous form at 200-500 °C. Dehydrated Ba(OH)2 activated at 200°C is denoted C-200. It is known to be a heterogeneous basic catalyst in the Horner-Wadsworth-Emmons (HWE) reaction of triethyl phosphonoacetate (69) with aldehydes 70 to give the 3-substituted ethyl acrylates 71 (Scheme 5.13) [35]. The HWE reaction proceeds at 70 °C in 1,4-dioxane with a small amount of water. The yields of products 71 are usually better than those provided by typical basic catalysts such as NaOH or... 

The Cs-phosphonate 39 is prepared by an Horner-Emmons reaction of triethyl-phosphonoacetate (11) with chloroacetone (40) in THE, with NaH or LDA as a base (yield 58%). The chloro product 47 is reacted with triethyl phosphite in an Arbusov reaction which gives, after distillation in vacuo, pure 39 in a yield of 81% [50] (Scheme 13). Similarly, diethyl cyanomethylphosphonate (3) is coupled to chloroacetone (40) in 72% yield and the coupling product 42 is converted into the C5-phosphonate 43 by reaction with triethyl phosphite. The yield after distillation is 89% [50]. 

C2]-Squalene, 80, has been produced71 in the reaction sequence shown in equation 31 which involves alkylation of 3-13C-ethyl acetoacetate with geranyl bromide, followed by hydrolysis, decarboxylation and treatment with triethyl phosphonoacetate and then reduction of the ester 82 with LiAlHr, bromination with CBr4/PPh3 and coupling the farnesyl bromide with Cul/Li-pyrrolidine. Epoxidation of 80 has been effected by... 

The catalytic asymmetric Horner-Wadsworth-Emmons reaction was realized by use of the quaternary ammonium salts 7 derived from cinchonine as a phase transfer catalyst.1631 Thus, tert-butylcyclo-hexanone 85 reacted with triethyl phosphonoacet-ate 86 together with RbOH-H20 in the presence of the ammonium salts 7, and then the product 87 was isolated after reesterification by treatment with acidic ethanol, as shown in Scheme 27 Among the... 

The Wittig-Horner (W-H) reaction is a versatile method for the synthesis of functionalized alkenes. The synthesis of 3-substituted ethyl acrylates and acrylonitriles, which are used as monomers in polymerization, were successfully carried out by the reaction of triethyl phosphonoacetate or cyanomethanephosphonate, respectively, with various aldehydes with activated Ba(OH)2 as the catalyst in the presence of dioxane solvent at 343 K (294). As was observed for other basic solid... 

The condensation of 5-acetyl derivative 404 instead of the corresponding 5-formyl compound, with ethyl acetoace-tate, ethyl benzoylacetate, and diethyl acetone-1,3-dicarboxylate, by heating in the absence of base gave the respective 6-acylpyrido[2,3-4]pyrimidin-7(8//)-ones 406. The reaction of 404 with diethyl malonate afforded the 6-carboxylate 407 <2005RCB784>. Reaction of 405 with triethyl phosphonoacetate yielded 408 <2001W02001070741>. 

Ethyl oL-(hydroxymethyl)acrylate.3 This useful acrylate (2) can be prepared in —75% yield by reaction of triethyl phosphonoacetate with a 30% aqueous solution of formaldehyde. It is converted to ethyl a-(bromomethyl)acrylate by reaction with PBr3 in ether (—85% yield). 

Triethyl phosphonoacetate (11.2 g, 0.05 mol) is added dropwise at 20 °C to a slurry of 50 per cent sodium hydride (2.4 g, 0.05 mol) in 100 ml of dry 1,2-dimethoxyethane. After the addition, the reaction mixture is stirred for 1 hour at room temperature until gas evolution has ceased. Cyclohexanone (4.9 g, 0.05 mol) is added dropwise at such a rate that the temperature is maintained below 30 °C. After the addition, the solution is stirred for 15 minutes at room temperature during which time a viscous semi-solid appears. The mixture is taken up in a large excess of water, and the aqueous solution extracted with ether. The ether layer, after being dried over magnesium sulphate and evaporated, gives a liquid residue, b.p. 88-90 °C/10mmHg, 5.8 g (70%), 1.4704. 

Cognate preparation. Ethyl (E)-but-2-enoate255 (PTC procedure). A solution of triethyl phosphonoacetate (35 mmol) and acetaldehyde (35 mmol) in dichloromethane (5 ml) is added dropwise to a stirred two-phase system consisting of dichloromethane (35 ml), aqueous sodium hydroxide (20 ml, 50%) and tetrabutylammonium iodide (0.7 g) (1). The strongly exothermic reaction is complete in 15 minutes. The organic layer is separated, washed with water (5 ml), and dried with magnesium sulphate. Evaporation of the solvent and distillation of the residue affords the product, b.p. 51-52 °C/25mmHg, in 54 per cent yield. 

Polyester divinylstilbene brighteners with a very high efficiency [37] include 4,4 -bis(ethoxycarbonylvinyl)stilbene (13) [60683-03-6], which can be obtained by the reaction of stilbene-4,4 -dicarbaldehyde with triethyl phosphonoacetate in the presence of sodium methoxide. 

The protected methyl glycoside 3 is converted to the corresponding aldehyde by Swern oxidation using oxalyl chloride activated DMSO. Further reaction with triethyl phosphonoacetate and sodium hydride -known as the Horner-Wadsworth-Emmons reaction - provides selectively the trans et /Tun saturated ester 4 in 72 % yield. This valuable alternative to the Wittig olefination protocol uses phosphonate esters as substrates which are readily available from alkyl halides and trialkyl phosphites via the Arbuzov rearrangement.9 co2Et Reaction of the phosphonate with a suitable base gives the... 

Pyrimido[5,4-c]-l,2,5-oxadiazinones (417) are suitable starting materials to construct annulated pyrazines. Reaction with carbanions derived from CH-acidic compounds, activated by two different electron-withdrawing functions, proceed in a regioselective manner by initial attack at the N—O bond. Triethyl phosphonoacetate, /f-ketophosphonates, nitro ketones, nitro esters, sulfonylacetates, and JV-acetoacetylglycine have been applied to form 6,7-disubstituted lumazines (418) (Equation (18)) <91H(32)79>. 

The combination of these compounds will generate cinnamic acid through the synthetic sequence illustrated below. As shown, benzyl alcohol is oxidized to benzal-dehyde using the Swem oxidation. Next, the aldehyde is reacted with triethyl phosphonoacetate by applying the Homer-Emmons reaction. Finally, the ester is hydrolyzed to a carboxylic acid. With arrow pushing, the mechanism for the... 

Their synthetic approach for the construction of the tetrahydrofuranone ring started with 7-cyanoheptanal79 98 which was converted in the first step into 9-cyano-2-nonenoate 99 by reaction with sodium triethyl phosphonoacetate. 

The 1-phenyl 3-carboxaldehyde (148, R = H, R = Ph) underwent reaction at 20° with diethyl malonate in ether, to which one drop of piperidine was added, to give the methylenemalonate (151) (90%). Alkaline hydrolysis gave the diacid (153) (70%), which was de-carboxylated in refluxing hydrochloric acid to the jS-acrylic acid (154) (83 %). A Wittig reaction of the aldehyde (148, R = H, R = Ph) with triethyl phosphonoacetate and sodium ethoxide in DMF at 10° gave the ethyl acrylate (152, 46%), which was hydrolyzed also to the acid (154) (78%).i 9... 

A repetition of the reaction of triethyl phosphonoacetate with trifluoromethanesulfonyl azide gave exclusively the diazo transfer product rather than the azide as reported in reference 309. Charette, A. B. Marcoux, D. Department de Chimie, University de Montreal, Montreal, Canada. Personal communication, 2007. 

---