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We present an efficient synthesis of beta-hydroxyesters and alpha,beta-unsaturated esters via activation of the silicon-carbon bond of alpha-trimethylsilylethylacetate using catalytic amounts of the commercially available P(i-PrNCH(2)CH(2))(3)N 1a. Selectivity for either of these two products can be achieved simply by altering the catalyst loading and reaction temperature to afford addition or stereoselective condensation. This method is mild and tolerates a wide array of functional groups.

Ethanol production from corn starch in the corn dry milling process leaves Distillers' Dry Grains and Solubles (DDGS) as a major by-product from which additional ethanol may be economically obtained from its glucan content. A challenge in processing the cellulose content of this material lies in its extensive inter-cellulose chain hydrogen bonding, which inhibits access of enzymes capable of cleaving glycosidic bonds, a transformation required for providing fermentable sugars. The phosphitylation of cellulosic OH groups using a reactive bicyclic phosphite ester is utilized to disrupt cellulosic hydrogen bonds, thus providing access to cellulose chains for further processing. We describe a method of pretreating DDGS with commercially available trimethylolpropane phosphite [P(OCH2)3CEt] in the presence of a slight molar excess of water to afford greater than 90% DDGS solubility in the reaction mixture in methanol and in water. Preliminary results using a model compound [D-(+)-permethylated cellobiose] indicate that glycosidic bonds are cleaved as a consequence of this pretreatment.

We present an efficient synthesis of β-hydroxyesters and α,β- unsaturated esters via activation of the silicon-carbon bond of α-trimethylsilylethylacetate using catalytic amounts of the commercially available P(i-PrNCH2CH2)3N 1a. Selectivity for either of these two products can be achieved simply by altering the catalyst loading and reaction temperature to afford addition or stereoselective condensation. This method is mild and tolerates a wide array of functional groups. [ABSTRACT FROM AUTHOR]

Examines the role of iminophosphorane as catalyst in the acylation of primary alcohols using enol esters. Survival of acid labile groups under reaction conditions; Relevance of acyl group on alcohols; Effect of protecting primary alcohol in the presence of secondary alcohol; Application of polymer-supported catalysts in industries.

Describes the synthesis of the phosphate ester 1-oxo-2-oxa-1-phosphabicyclo[2.2.2]octane from hypophosphorous acid. Molecular structure; Comparison with the bicyclic phosphate OP(OCH2)3CCH3; Hydrolysis of the ester; Crystal structure analysis; Calculated enthalpies, entropies, and free energies of activation for the hydrolysis of the ester.

Describes the synthesis of oxazoles and alpha-C-acyl amino acid esters. Synthesis of alpha-(alkoxycarbonyl) pyrrole and dipyrromethane derivatives; Preparation of alpha-unsubstituted pyrrole derivative 23; Synthesis of porphyrins.

Merrifield resin-supported N3ᆖP(MeNCH2CH2)3N shows excellent activity in the transesterification of higher esters such as glyceryl tribenzoate to methyl esters. The catalyst was successfully cycled 20 times (albeit with an increase in reaction time) without compromising yield up to the 20th cycle. The catalyst also showed good performance in amidation reactions of unactivated esters with amino alcohols. [ABSTRACT FROM AUTHOR]

Examines the effects of adding primary alcohols,higher nitroalkanes and &alpha7-amino ester Schiff base to α,β-unsaturated substrates. Diastereoselectivity level of Schiff base in the absence of lithium ion; Use of silica gel column filtration in catalysts removal; Effectiveness of Michael addition in calcium-C bonds formation.