Esters greening

Beckman EJ, Munshi P (2011) Ambient caiboxylation on a supported reversible C02 carrier ketone to [beta]-keto ester. Green Chem 13(2) 376-383... 

Villa, C., E. Mariani, A. Loupy, C. Grippo, G.C. Grossi and A. Bargagna, Solvent-Free Reactions as Green Chemistry Procedures for the Synthesis of Cosmetic Fatty Esters, Green Chemistry, 5, 623-626 (2003). 

Table 5.3 Industrial uses of esteric green solvents.

Mutschler J, Rausis T, Bourgeois J-M et ai (2009) Ionic liquid-coated immobilized lipase for the synthesis of methylglucose fatty acid esters. Green Chem 11 1793-1800... 

Sharma, B.K. K.M. Doll S.Z. Erhan. Oxidation, friction reducing, and low temperature properties of epoxy fatty acid methyl esters. Green Chem. 2007a, 9, 469-474. 

Spex 8000M mixer mill, stainless steel vial and ball (5mm), 18Hz, stainless steel ball (5mm). Reproduced from Shearouse WC, Korte CM, Mack J. A two-step ball milling method synthesizes and purifies a,p-unsaturated esters. Green Chem 2011 13.598-601, with permission from the Royal Socsty of Chemistry. 

Reproduced from Mack J, Fuimer D, Stolel S, Santos N. The first solvent-free method for the reduction of esters. Green Chem 2007 1041-3, with permission from the Royal Society of... 

Shearouse WC, Korte CM, Mack J. A two-step ball milling method synthesizes and purifies a,p-unsaturated esters. Green Chem 2011 13 598-601. 

Esters Green (a) Yellow (b) Dun (b) Marrowfat (c) Meath Park (a) Wilkie (a)... 

To 2 ml. of the ester in a test-tube add slightly more than the same volume of a cold saturated aqueous copper acetate solution. The blue colour of the latter turns immediately to a pale green. Now shake the tube vigorously in order to produce an emulsion of the ester in the aqueous layer. Scratch the sides of the tube with a rod, and shake vigorously as before. Crystallisation may be delayed for about 5 minutes, but, when once started, rapidly gives a copious precipitate... 

As a general guide, however, it may be noted that the following have fairly easily recognisable odours methyl and ethyl formate methyl and ethyl acetate (apples) methyl and ethyl benzoate methyl salicylate (oil of winter-green) and ethyl salicylate methyl and ethyl cinnamate. (It is however usually impracticable to distinguish by odour alone between the methyl and ethyl esters of a particular acid.) Methyl and ethyl o. alate, and methyl and ethyl phthalate are almost odourless. Succinic and tartaric esters have faint odours. 

Some straightforward, efficient cyclopentanellation procedures were developed recently. Addition of a malonic ester anion to a cyclopropane-1,1-dicarboxylic ester followed by a Dieckmann condensation (S. Danishefsky, 1974) or addition of iJ-ketoester anions to a (l-phenylthiocyclopropyl)phosphonium cation followed by intramolecular Wittig reaction (J.P, Marino. 1975) produced cyclopentanones. Another procedure starts with a (2 + 21-cycloaddition of dichloroketene to alkenes followed by regioselective ring expansion with diazomethane. The resulting 2,2-dichlorocyclopentanones can be converted to a large variety of cyclopentane derivatives (A.E. Greene. 1979 J.-P. Deprds, 1980). 

Volatiles or Aroma. The essential oil, or aroma, of tea provides much of the pleasing flavor and scent of green and black tea beverages. Despite this, volatile components comprise only - 1% of the total mass of the tea leaves and tea infusions. Black tea aroma contains over 300 characterizing compounds, the most important of which are terpenes, terpene alcohols, lactones, ketones, esters, and spiro compounds (30). The mechanisms for the formation of these important tea compounds are not fully understood. The respective chemistries of the aroma constituents of tea have been reviewed... 

Rosenheim reaction CHCI3 + lead tetraacetate in green fluorescence not given by esters of provitamin D can... 

Bayberry Wax. Bayberry wax [8038-77-5] is removed from the surface of the berry of the bayberry (myrtle) shmb by boiling the berries in water and skimming the wax from the surface of the water. The wax is green and made up primarily of lauric, myristic, and palmitic acid esters. The wax has a melting point of 45°C, an acid number of 15, a saponification number of 220, and an iodine number of 6. The wax has an aromatic odor and is used primarily in the manufacture of candles and other products where the distinctive odor is desirable. 

Potassium sodium copper chlorophyllin (chiorophyllin—copper complex)—A green-black powder obtained from chlorophyll by replacing the methyl and phytyl ester groups with alkaH and replacing the magnesium with copper. The source of the chlorophyll is dehydrated alfalfa. 

Brilliant green neutral esters of phosphoric acid [125], carbamate herbicides [34]... 

For the determination of sterols and their esters the chromatogram is immersed in a 10% aqueous copper(II) sulfate solution and then heated to 105°C for 30 min. In this case green-yellow fluorescent chromatogram zones are visible in long-wavelength UV light (X = 365 nm) [6]. 

Add I c.c. of a saturated alcoholic solution of cupric acetate to a few drops of the ester, a bluish-green crystalline precipitate of copper acetoacetic ester, (CoH903), Cu, is formed. See Appendix, p. 248. i . ... 

It is thus apparent that at the commencement of vegetation of the peppermint the oil is rich in menthol, hut only a small amount is present in the esterified condition. Menthone only exists in small quantity. As the green parts of the plant develope, the proportion of esterified menthol increases, as has heen found to be the case with other alcohols. This esterification, however, only takes place in the leaves, and when the essential oil extends towards the flowering tops, it becomes poorer in esters. 

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