Carboxyiate ester, 97

The Conversion of Anhydrides, Carboxyiic Esters, or Amides to Ketones With Organometaiiic Compounds ... 

Oxidation of Ethers to Carboxyiic Esters and Related Reactions... 

Oxidation of Primary Alcohols to Carboxylic Acids or Carboxyiic Esters... 

Dialkylboron trifluoromethanesulfonates (Inflates) are particularly useful reagents for the preparation of boron enolates from carbonyl compounds, including ketones, thioesters and acyloxazoiidinones. Recentiy, the combination of dicylohexyiboron trifluoromethanesulfonate and triethyiamine was found to effect the enolization of carboxyiic esters. The boron-mediated asymmetric aldoi reaction of carboxyiic esters is particuiariy usefui for the construction of anti p-hydroxy-a-melhyl carbonyl units. The present procedure is a siight modification of that reported by Brown, et ai. ... 

See the procedure describing the anti-selective asymmetric aldol reaction of carboxyiic esters, p. 116. 

Zwanenburg, B., ten Hoite, P. The synthetic potentiai of three-membered ring aza-heterocycies. Top. Curr. Chem. 2001, 216, 93-124. Bonini, B. F., Fochi, M., Comes-Franchini, M., Ricci, A., Thijs, L., Zwanenburg, B. Synthesis of ferrocenyi-oxazoiines by ring expansion of N-ferrocenoyi-aziridine-2-carboxyiic esters. Tetrahedron Asymmetry 2003, 14, 3321-3327. 

Noyori, R., Ohkuma, T., Kitamura, M., Takaya, H., Sayo, N., Kumobayashi, H., Akutagawa, S. Asymmetric hydrogenation of 3-keto carboxyiic esters. A practicai, pureiy chemicai access to P-hydroxy esters in high enantiomeric purity. J. Am. Chem. Soc. 1987, 109, 5856-5858. 

Figure 3-5. The search for a) oxidations of primary alcohols to carboxylic acids will obtain reaction b) as a hit, although this reaction is in reality a hydrolysis of an ester, c) The correct specification of the query to obtain reactions invoivingthe oxidation of aicohols to carboxyiic acids.

Metal carboxyiates have been considered as nucleophilic agents capable of removing aHyUc chlorine and thereby affording stabilization (143). Typical PVC stabilizers, eg, tin, lead, or cadmium esters, actually promote the degradation of VDC polymers. The metal cations in these compounds are much too acidic to be used with VDC polymers. An effective carboxylate stabilizer must contain a metal cation sufftcientiy acidic to interact with aHyUc chlorine and to facihtate its displacement by the carboxylate anion, but at the same time not acidic enough to strip chlorine from the polymer main chain (144). 

Isocoumarin-3-carboxyIic acid, 8-methoxy-synthesis, 3, 834 Isocoumarin-4-carboxylic acid methyl ester synthesis, 3, 832... 

IsothiazoIe-5-carboxyIic acid, 3-methyI-bromination, S, 58 Isothiazolecarboxylic acid chlorides Amdt-Eistert reaction, 6, 157 Reissert reactions, 6, 157 Isothiazolecarboxylic acids esters... 

IsoxazoIe-3-carboxyIic acid, 5-phenyI-silver salt reactions, 6, 52 synthesis, 6, 85 IsoxazoIe-4-carboxyIic acid esters... 

IsoxazoIe-4-carboxyIic acid, 3-ethyl-5-methyI-ethyl ester... 

IsoxazoIe-5-carboxyIic acid anilide, 3,4-diphenyI-synthesis, 6, 86 Isoxazolecarboxylic acids applications, 6, 128 IR spectra, 6, 5 potentiometry, 6, 11 reactions, 6, 52 synthesis, 6,27, 85-86 thermochemistry, 6, 10 IsoxazoIe-3,4-dicarboxyIic acid esters... 

The use of HMDS (ca. 1.5 mmol) and saccharin (0.01 mmol) per mmol of substrate in refluxing dichloromethane or chloroform has been recommended (5) for easy silylation of carboxylic acids, including azetidin-2-one-4-carboxyIic acids. Clear solutions result, i.e., no ammonium salts are present at completion of the reaction, and consequently the silyl esters can be obtained by direct distillation, or merely by evaporation of solvent. 

I CN l-(3-cyano-3,3-diphenylpropyl)-4-phenylpiperidine-4-carboxyIic acid ethyl ester hydrochloride... 

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