Dibenzoate ester

The largest use for benzoic acid is as a chemical raw material in the production of phenol, caprolactam, glycol dibenzoate esters, and sodium and/or potassium benzoate. 

In an effort to obtain a salvinorin derivative possessing an oe-diol system which can be transformed into the dibenzoate ester required for the exciton chirality CD method, salvinorin A (1) or B (2) was treated with sodium borohydride in various protic solvents. The products having the la,2a-diol group were obtained in high yield. However, this reduction was accompanied by extensive isomerization at C-8. While mechanistic details for this unexpected observation remain to be established at this time, the isomerization at C-8 appears to be the result of the base-promoted clevage of the C-8/9 bond under the reaction conditions followed by the reclosure to provide the 8-epimer prior to the reduction of the 1-ketone. Furthermore, attempts to obtain the 1,2-dibenzoate derivative of the major reduction product 3 under various benzoylating conditions invariably produced only the 2-monobenzoate. 

Preparation 214.—Mannitol Dibenzoate [1 6-Dibenzoic ester ofhexol-... 

Benzoflex [Velsicol], TM for a series of plasticizers that are dibenzoate esters of dipropylene glycol or any of several polyethylene glycols. Use Primary plasticizer for vinyl resins adhesive formulations some grades in food-packaging adhesives. 

The Bristol-Meyers Squibb company wanted the simple heterocycle 8 for the preparation of a tryptase inhibitor. As 8 is an amine, tartaric acid was the first choice for a resolving agent. It again turned out that a modified version of the first choice was the best. Tartaric acid is so good at resolutions that simple variations, such as the dibenzoate ester 9, often work well. 

Fast-fusing plasticizers enable the PVC material to be processed faster or at lower temperatures. Generally it is in the area of plasfisol applications where the uses of faster fusing plasticizers are preferred. Examples of fast-fiising plasticizers include butyl benzyl phthalate (BBP), citrates, the epoxidized fatty acid plasticizer methyl epoxy stearate, alkyl sulfonic acid esters of phenol, dibutyl phthalates and tere-phthalates, and dibenzoate esters and benzoate ester blends. It should be noted that the use of BBP in PVC has rapidly declined because of product restrictions, while the use of dibutyl phthalate (DBP) declined in North America and in Europe years ago because of its high volatility. 

Monobenzoate esters are prepared by the esterification of benzoic acid with one molar equivalent of alcohol, usually 2-ethylhexanol, isononanol, or isodecanol. Monobenzoates are not used as primary plasticizers but as secondary plasticizers where they help reduce plastisol viscosities, lower the fusion or processing temperatures, and give a boost to stain resistance in formulations based on GP plasticizers. Both mono and dibenzoate esters can be used in non-PVC materials such as acrylic films and caulks, latex coatings, polysulfide sealants and coatings, and polyurethanes. 

Plasticizers can be used to reduce both the viscosity and the cost of polyurethane and polysullide automotive and construction sealants. Higher molecular weight phthalate esters such as DINP, DIDP, and DUP or LI IP are generally suitable for most polyurethane sealant applications. Polysullide sealants require more polar plasticizers such as the alkyl benzyl phthalates, alkyl sulfonic acid esters, or dibenzoate esters. Recently the application of castor oil based plasticizers for polyurethanes has been described [46]. 

K-Flex dibenzoate esters are widely used as plasticizers for polyvinyl acetate emulsion systems. In these systems, K-Flex dibenzoate esters reduce set times, increase open time, increase film flexibility, reduce heat sealing tea eratures, and ia rove the dried film s resistance to oil, grease, and water. They also serve to enhance solution viscosities, often eliminating the need for other additives. K-Flex dibenzoate esters offer equal or superior performance to other recognized adhesive plasticizers. 

K-Flex dibenzoate esters are compatible with many other polymeric ziaterials including ethylene vinyl acetate (EVA), polyvinyl chloride (PVC), styrene-butadiene rubber (8BR), ethyl cellulose, nitrocellulose, cellulose acetate butyrate, nitrile rubber, and acrylics. 

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