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An efficient intermolecular conjugate addition of alcohols was developed to activate the alkenes catalyzed by N-heterocyclic carbenes. IMes also catalyze the formation of vinyl ethers through the 1,4-addition of alcohols to ynones and promotes tandem conjugate addition/Michael cascade reactions in addition to reaction with activated alkenes.

A new approach is described that has taken advantage of N-heterocyclic carbene/Lewis acid cooperative catalysis to provide access to cis-1,3,4-trisubstituted cyclopentenes from enals and chalcone derivatives with high levels of diastereoselectivity and enantioselectivity. The studies have shown the possibility of controlling the absolute stereochemistry of NHC-catalyzed reactions by using a catalytic amount of a chiral Lewis acid as the unique source of optically active promoter.

A new method was designed for the synthesis of enantioenriched indanones by asymmetric carbonyl-ene/intramolecular Heck cyclization from racemic silyloxyallenes. Short reaction times and high yields of the modular procedure is demonstrated by production of highly substituted indenes and indanones with excellent chirality transfer from the optically active carbinols.

N-Heterocyclic carbenes (NHCs) have catalyzed a new Mannich-type reaction to form [beta]-amino acid derivatives in high yield and enantioselectivity. The activated ester products formed in situ have formed a variety of useful compounds including [beta]-amino acids, [beta]-amino amides and peptides.

The total synthesis and biological evaluation of neopeltolide and analogs are described. The biological data of the analogs have shown that alterations to either the ester side chain or the stereochemistry of the macrolide have resulted in a loss of biological activity.

A novel approach to construct structural motifs of [beta]-hydroxy carbonyl compounds has involved the multicomponent reaction of acylsilanes, amide and electrophiles. The addition of amide enolates to acylsilanes has generated [beta]-silyloxy homoenolate reactivity by undergoing a 1,2-Brook rearrangement and the optically active amide enolates has delivered [beta]-hydroxy amide products with high levels of diastereoselectivity.

Nonlinear optics are used for showing that acid-base chemistry at aqueous/solid interfaces has tracked bulk pH changes at low salt concentrations. The studies have shown that for pH cycling in these systems, the interspatial systems can spatially and temporally lag bulk acid-base chemistry when the Debye length has approached 1 nm.

The catalytic amination of homoenolates is described by combining [alpha],[beta]-unsaturated aldehydes with diazenes in the presence of N-heterocyclic carbenes (NHCs) to produce pyrazolidinones. A chiral triazolium salt is used for controlling the newly formed stereocenter of the product and the pyrazolidione products are converted into [beta]-amino acid derivatives.

The total synthesis and the structural properties of the marine macrolide neopeltolide are discussed. The methodology used for the synthesis is shown to be highly flexible and hence can be used for the synthesis of various natural product targets.

A frequency domain approach is used for proving the existence of single-molecule surface-enhanced Raman spectroscopy (SMSERS). The existence is demonstrated by using two isotopologues of Rhodamine 6G offering unique vibrational signatures.

The enantioselective synthesis of [alpha],[ alpha]-disubstituted cyclopentenes by an intramolecular aldol reaction of achiral tricarbonyl compounds catalyzed by chiral N-heterocyclic carbenes is presented.

A series of [beta]-substituted [alpha],[beta]-unsaturated phosphonates and [alpha],[beta]-unsaturated 2-acyl imidazoles are used for the enantioselective Friedel-Crafts addition of a variety of indoles catalyzed by bis(oxazolinyl)pyridine-scandium(III) triflate complexes (Sc(III)-pybox). The nonlinear effects over a range of catalyst concentrations have implicated a mononuclear complex as the active catalyst.

The first formal [3+3] cycloaddition reaction of aldehyde and azomethine imines catalyzed by N-heterocyclic carbenes (NHCs) is developed. The pyridazinone products can produce esters or amides in excellent yields upon addition of alcohols or amines.

A study shows that silyloxyallenes generated from acylsilanes undergo scandium (III)-catalyzed [alpha]-acylvinyl additions to a variety of aldehydes. Results reveal that a wide range of [Beta]-substitution on the alleric is accommodated with excellent yields and a high degree of control over the new alkene geometry, and the carbinol stereocenter of the resulting unsaturated ketone products can be controlled by a chiral catalyst.

The hydroacylation of alpha-keto esters with aldehydes catalyzed by N-heterocyclic carbenes is reported and for this process, the carbene facilitates selective catalytic oxidation of a C--H bond with concomitant reduction of a ketone. Substituted aromatic keto esters provide the desired esters resulting from overall hydroacylation in good yield when dichloromethane is used as the solvent.

A robust catalytic carbonyl anion reaction that is fully operative over a broad range of pH values is developed. Under neutral aqueous conditions, the combination of alpha-keto carboxylates and thiazolium salts produces reactive carbonyl nucleophiles that readily undergo conjugate additions to versatile beta-substituted unsaturated 2-acyl imidazoles.

A new silyl variant of the stetter reaction between acylsilanes and alpha, beta-unsaturated conjugate acceptors promoted by an organic catalyst is disclosed. Table showing influence of acylsilane structures of acyl anion reaction is presented.

The copper(I) catalyzed disilylation of alkylidene malonates with disilanes in the presence of Lewis bases to yield functionalized beta-silyl diesters is mentioned. The copper(I) catalyzed disilylation of alkylidene malonates is explained.

The highly diastereo- and enantioselective combination of [alpha],[beta]-unsaturated aldehydes with nitrones catalyzed by N-heterocyclic carbenes to yield [gamma]-amino esters upon the addition of an alcohol is described. N-heterocyclic carbene catalysis is shown as a powerful method that has provided new directions for the synthesis through innovative bond construction.

The direct synthesis of [alpha]-aryl ketones by the acylation of o-quinone methides is presented. A reactive carbonyl anion and o-quinone methide are generated by the addition of fluoride ion and have undergone productive bond formation to yield the desired adducts in the umpolung process.

The first direct nucleophilic acylation of nitroalkenes to produce beta-nitro ketones by the combination of a fluoride source with silylated thiazolium carbinols are described. The distinct fluoride-activated acyl anion strategy is divergent from the typical combinations of heteroazolium salts and bases and thus allows for the use of reactive nitroalkenes as substrates.

The utility of the chiral scandium complex in the catalyzed additions of electron-rich aromatic substrates to alpha,beta-unsaturated acyl phosphonates is described. Scandium-pybox complexes are efficient catalysts for the Friedel-Crafts additions of electron-rich aromatic nucleophiles to alpha,beta-unsaturated acyl phosphonates.

A study was conducted to screen vinyl sulfonate ester and vinyl sulfonamide inhibitors to characterize potent and selective inhibitors of cruzain. Several aryl sulfonate esters were analyzed in the study. Results indicated that benzyl vinyl sulfone is a potent enzyme inhibitor of cruzain and that vinyl sulfonamides and sulfonate esters are time-dependent inhibitors of cruzain. Findings also showed that maximal activity is determined when the one-atom spacer is an oxygen atom.