Jerzy A. Krysiak

1,3-Dipolar cycloaddition of diazoalkanes to racemic and optically active α-(diethoxyphosphoryl)vinyl p-tolyl sulfoxides: a new synthesis of 3-phosphorylpyrazoles and asymmetric synthesis of cyclopropanes

Abstract Cycloaddition of diazomethane and ethyl diazoacetate to α-(diethoxyphosphoryl)vinyl p-tolyl sulfoxide 1a and its β-substituted analogues (Me, Ph) results in the formation of 3-phosphoryl-pyrazoles in high yield. The reaction ofchiral (S)-(+)-1a with diphenyldiazomethane proceeds fully diastereoselectively to give the corresponding cyclopropane (+)-6a with the (Sc, SS) configuration determined by X-ray diffraction analysis. Diazopropane reacts with (S)-(+)-1a to give only one diastereoisomer of the pyrazoline cycloadduct (+)-2e which undergoes decomposition to the cyclopropane (+)-6b with preservation of configurational integrity.

The first synthesis of enantiomerically pure cyclopropylphosphonate analogues of nucleotides via asymmetric cyclopropanation of chiral (1-diethoxyphosphoryl)vinyl p-tolyl sulfoxide

(S)-(+)-(1-Diethoxyphosphoryl)vinyl p-tolyl sulfoxide undergoes cyclopropanation with ethyl (dimethylsulfuranylidene)acetate (EDSA) in a highly diastereoselective manner (facial stereoselectivity up to 12:1). The major diastereomer obtained in this reaction, (1S,2S)-(1-diethoxyphosphoryl-2-ethoxycarbonyl)cyclopropyl p-tolyl sulfoxide, was converted in three steps into enantiopure cyclopropylphosphonate analogues of purine nucleotides as the constrained forms of antiviral 1-alkenylphosphonic acid derivatives of purines.

α-phosphoryl sulfoxides. X. A general synthesis of optically active α-chlorovinyl sulfoxides

Abstract A general and efficient synthesis of enantiomeric α-chlorovinyl p-tolyl sulfoxides 1 using (+)-(S) C (S) S -α-chloro-α-dimethoxyphosphorylmethyl p-tolyl sulfoxide as a key substrate for the Horner-Wittig reaction with carbonyl compounds is described. The E Z ratio of geometrical isomers of 1 was determined and briefly investigated. The X-ray diffraction structures of ( Z )-1-chloro-1-p-tolylsulfinyl-2-phenyl-ethene and (Z)-1-chloro-1-p-tolylsulfinyl-2-(2-thienyl)-ethene are reported.

Application of organolithium and related reagents in synthesis. Part 14. Synthetic strategies based on aromatic metallation. A concise regiospecific conversion of benzoic acids into their ortho-pyridoyl derivatives

Abstract The synthesis of the 3-hydroxy-3-pyridyl-isoindolin-1-ones ( 5 ) and ( 6 ) via metallation (n-BuLi) of the benzanilides ( 1 ), and then the reaction of the generated bis lithiated anilides ( 2 ) with N,N-dimethylamides or methyl esters of pyridinecarboxylic acids (benzoylation reagents), and subsequent acidic hydrolysis of ( 5 ) and ( 6 ) as a way (general synthetic strategy) of regiospecific transformation of benzoic acids into their ortho-benzoylated derivatives, is described.

Unusual behavior of phosphonocyclopropyl sulfoxides

GRAPHICAL ABSTRACT ABSTRACT Synthesis of acylated phosphonocyclopropyl sulfoxide was performed in order to confirm some mechanistic aspects of 1,2 phosphoryl group migration. Reduction using phenylsilane in the KOH-catalyzed system was applied successfully for the conversion of carboalkoxy group to the corresponding alcohol. However, when both carboalkoxy and sulfinyl substituents were present at the same carbon atom, desulfinylation product was observed.

Highly Asymmetric Cyclopropanation With Two Sulfinyl Auxiliaries as a Way to a Useful Synthetic Intermediate

The asymmetric cyclopropanation using double sulfinyl auxiliary gave bis-sulfoxide with full diastereoselectivity and very high enantioselectivity. One of the sulfinyl substituents can be removed by sulfinyl metal exchange. Differentiation of sulfinyl substituents made it possible to assign the place of attack of the Grignard reagent.

Asymmetric Synthesis of Cyclopropane Phosphonates as A Route To 2-Substituted Cyclopropylglycine, Antagonist of Metabotropic Receptors

Abstract We describe two attempts to the synthesis of novel constrained L-AP4 analogs of potential antagonist activity. Although the first approach to introduce alkyl substituent on the amino acid carbon using cyclopropyl keton failed, conversion of cyclopropanecarboxylate into corresponding β-ketophosphonate is promising and more general. GRAPHICAL ABSTRACT