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Research has been conducted on the trifluoro- and and monofluoro frontalin enantiomers. The results of the stereoselective synthesis of these enantiomers which are the bioactive component analogues of the Scolytidae insect family aggregation pheromone are reported.

Research has been conducted on the nonproteinogenic acid statine contained in the microbial aspartyl protease inhibitors. The stereocontrolled synthesis of the statine's enantiomers has been carried out and the results are reported.

Research describes a new simple high-yielding synthetic route for the synthesis of racemic orthogonally protected alpha-(trifluoromethyl)-and alpha-(difluoromethyl)arginines. Data reveal that the synthesis essentially proceeds in two key steps of mild guanidinylation and selective hydrogenation of a CC triple bond.

Research discusses the stereoselectivity of the Pummerer reaction and its application for the synthesis of densely functionalized L-alpha-trifluoromethyl (Tfm)-threoninate and D-alpha-Tfm-allo-threoninate in one-pot protocol involving treatment of the diasteromeric sulfenamides with sodium borohydride.

Research has been conducted on the synthesis of D-erythro-alpha-Tfm-beta-hydroxyaspartic units to investigate a streoselective Mannich-type reaction of the chlorotitanium enolate of (alpha-benzyloxy)acetyl 2-oxazolidinone with N-Cbz-imine of ethyl trifluoropyruvate. The use of 2-oxazolidinone ring system as a chiral auxiliary is analyzed.

A tandem sequential process that enhances the yields of fluoropyruvaldehyde N,S-ketals and ee from alpha-(fluoroalkyl)-beta-sulfinylenamines is developed. This process is characterized by a 1,2 migration of the p-tolylthio group preceded by a Pummerer reaction. Nuclear magnetic resonance spectroscopic analysis revealed the stability of imines in the reaction process.

The aza-Wittig reaction of triphenyliminophosphoranes with the corresponding alpha-fluorinated-alpha-sulfinyl ketones yields optically pure alpha-(fluoroalkyl)-beta-sulfinyl enamines. The fluorinated ketones are very reactive. Reaction of these chiral building blocks with some electrophiles, such as benzyl chloroformate, benzyl bromide, and allyl bromide, takes place at the nitrogen atom, producing the corresponding N,N-disubstituted enamines. These reactive ketones are useful as fluorinated nitrogen-substituted templates to synthesize biologically important fluorinated molecules.

Synthesis of enantiomerically pure selective fluorinated and polyhydroxylated cyclohexane derivatives involves the construction of ring from two fragments, with one having F atoms and two reactive Cl atoms and the second fragment having sulfinyl chiral auxiliary group and an unsaturation. A C-C forming ionic reaction joins the two fragments generating a fluorinated sulfinyl intermediate, forming monofluorocyclohexames through cyclization and reductive dehalogenation. Radical-induced cyclization of omega-dichlorofluoroheptenols generates gem-chlorofluorocyclohexanons.

Ethyl chlorodifluoroacetate is assembled with pent-6-en-1-yl p-tolyl sulfoxide to produce gem-difluoro-substituted and poly-functionalized cyclohexane derivatives which are enantiomerically pure. Base catalyzed condensation and radical-promoted cyclization lead to new carbon skeleton. The relative configuration of open-chain carbons, which are continuously substituted, influences the diastereoselection in the radical cyclization.

1,1-difluoroalkyl sulfinylmethyl ketones are ideal intermediates in the syntheses of difluoronated alcohol, ester, oxime, hydroxylamine and nitrile enantiomers. The ketones are first prepared via acylation of (+)-(R)-methyl 4-methylphenyl sulfoxide with alpha,alpha-difluoroesters. Reducing the keto forms yields the (2S,RsubS)-configured alcohols. Deoxygenation of the sulfoxide residue gives (S)-difluorosulfinylalkanols. Benzylation of the hydroxyl produces the benzyloxydifluorosulfinylalkanes, key intermediates in the synthesis of sulfur-free difluoro enantiomers. Other reactions yield their corresponding enantiomeric difluoro derivatives.

A thorough discussion on the reactivity of dimethyl sulfoxide (DMSO) of the transients from the reduction of daunomycin in one-electron step is presented. Reductions of the daunomycin is done either by sodium dithionite or bi(3,5,5-trimethyl-2-oxomorpholin-3-yl)(dl-TM-3 dimer). Results show that glyscosidic cleavage occurs at the hydroquinone state to from a relatively long quinone methide. It is concluded that the reduction of the DMSO is similar to the reductions of some known anthracyclines.

A novel method for the synthesis of enantiopure alpha-(fluoroalkyl) beta-sulfinyl amines was developed based on the asymmetric addition of alpha-lithiated alkylarylsulfoxides to (fluoroalkyl)aldimines. The synthetic strategy involved the preparation of imines based on direct condensation between p-anisidine and an aldehyde in the presence of a catalysts. The synthetic process was also characterized by the formation of two stereogenic centers during the condensation of the imines and the lithium derivative of Bn-p-tolylsulfoxide.

Reaction of 1H,1H-perfluoroalkyl iodides with a stoichiometric amount of chlorine at -196 degrees Celsius produces (dichloroiodo) 1H, 1H-perfluoroalkanes in good yields. The reaction is simple and the product exhibits high stability. Elemental analysis and spectral data help characterize the compounds. Chlorine-transfer and chlorine-exchange reactions confirm the formation of (dichloroido) 1H,1H-perfluoroalkanes.