1-chloroalkyl P-tolyl Sulfoxides Research Articles

A novel one-pot synthesis of cyclopropanols based on the reaction of magnesium carbenoids with lithium enolate of ketones

The reaction of magnesium carbenoids with lithium enolate of ketones resulted in the formation of cyclopropanols in moderate to good yields. These reactive species (i.e., magnesium carbenoids and lithium enolate of ketones) were generated from 1-chloroalkyl p-tolyl sulfoxides with i-PrMgCl and ketones with LDA in the reaction medium at −78°C in a one-pot reaction.

ChemInform Abstract: 1-Chloroalkyl p-Tolyl Sulfoxides as Useful Agents for Homologation of Carbonyl Compounds: Conversion of Carbonyl Compounds to α- Hydroxy Acids, Esters, and Amides and α,α′-Dihydroxy Ketones.

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カルベノイドの転位反応を活用するカルボニル化合物の増炭素法と最近の展開

One-carbon homologation or elongation of carbonyl compounds utilizing the rearrangement of carbenes or carbenoids as the key reaction is described. In the first chapter, one-carbon elongation of ketones and aldehydes, including one-carbon ring-expansion of cyclic ketones, by using dibromomethyllithium or lithium α-sulfinyl carbanion of 1-chloroalkyl p-tolyl sulfoxides as one-carbon homologating agents is discussed. The synthetic method for α-halo, α-sulfanyl, and α-sulfinyl carbonyl compounds from ketones and aldehydes with one-carbon elongation is summarized in the second chapter. In the third chapter, one-carbon elongation of carboxylic acids, esters, and acid chlorides to carboxylic acids and their derivatives by using dibromomethyllithium and lithium α-sulfinyl carbanion of chloromethyl p-tolyl sulfoxide as one-carbon homologating agents is discussed.

A new synthesis of cyclic α-amino acid derivatives by the intramolecular reaction of magnesium carbenoid with N-magnesio arylamine as the key reaction

A new synthesis of pipecolic acid and homopipecolic acid derivative was accomplished from 1-chloroalkyl p-tolyl sulfoxides having a 2-aminophenyl group at the ω-position by treatment with i-PrMgCl via the intramolecular reaction of magnesium carbenoid with N-magnesio arylamine. In a similar way, proline and pipecolic acid derivatives were synthesized from 1-chloroalkyl p-tolyl sulfoxides having an arylamino group at the ω-position.

A New Synthesis of 2-Sulfanyl Allylic Alcohols and .ALPHA.-Sulfanyl Ketones from Carbonyl Compounds and 1-Chloroalkyl p-Tolyl Sulfoxides with Carbon-Carbon Bond-Formation

Reaction of lithium alpha-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides with ketones or aldehydes at low temperature gave adducts in almost quantitative yields. Treatment of the adducts derived from ketones with trifluoroacetic anhydride (TFAA) in the presence of NaI in acetone gave alpha-sulfanyl allylic alcohols in good to quantitative yields. On the other hand, treatment of the adducts derived from aldehydes with TFAA and NaI resulted in the formation of alpha-sulfanyl ketones and/or alpha-sulfanyl allylic alcohols. These reactions offer a good method for the synthesis of the above-mentioned compounds from ketones and aldehydes with carbon-carbon bond-formation in two steps and in good yields.

A new method for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation through β-oxido carbenoid rearrangement as the key reaction

The addition reaction of carbonyl compounds with lithium α-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides gave adducts, α-chloro β-hydroxy sulfoxides, in high to quantitative yields. The adducts were first treated with a base to give alkoxides, which were treated with i-PrMgCl or t-BuLi to give β-oxido carbenoids via a sulfoxide–metal exchange reaction. The β-oxido carbenoid rearrangement then took place to afford the enolates with one-carbon elongation. The enolate intermediates were found to be able to be trapped with electrophiles such as aldehydes, ethyl chloroformate, benzoyl chloride, haloalkanes to give α,α-disubstituted carbonyl compounds in moderate to good yields. This method provides a new and efficient way for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation in only two synthetic operations.

A New Synthesis of α,α‐Disubstituted Carbonyl Compounds from Carbonyl Compounds with One‐Carbon Homologation.

Lithium α-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides were reacted with carbonyl compounds to afford adducts in high to quantitative yields. The adducts were treated with t-BuMgCl or LDA to give magnesium or lithium alkoxides, which were treated with i-PrMgCl or t-BuLi to afford the enolate with one-carbon elongation through β-oxido carbenoids. The enolate intermediates were found to be able to be trapped with electrophiles to give α,α-disubstituted carbonyl compounds in moderate to good yields. As a whole, this procedure offers a new and good method for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation in only two synthetic steps.

A new synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation

Lithium α-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides were reacted with carbonyl compounds to afford adducts in high to quantitative yields. The adducts were treated with t-BuMgCl or LDA to give magnesium or lithium alkoxides, which were treated with i-PrMgCl or t-BuLi to afford the enolate with one-carbon elongation through β-oxido carbenoids. The enolate intermediates were found to be able to be trapped with electrophiles to give α,α-disubstituted carbonyl compounds in moderate to good yields. As a whole, this procedure offers a new and good method for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation in only two synthetic steps.

A new synthesis of $alpha;,$alpha;-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation

Lithium α-sulfinyl carbanions of 1-chloroalkyl p-tolyl sulfoxides were reacted with carbonyl compounds to afford adducts in high to quantitative yields. The adducts were treated with t-BuMgCl or LDA to give magnesium or lithium alkoxides, which were treated with i-PrMgCl or t-BuLi to afford the enolate with one-carbon elongation through β-oxido carbenoids. The enolate intermediates were found to be able to be trapped with electrophiles to give α,α-disubstituted carbonyl compounds in moderate to good yields. As a whole, this procedure offers a new and good method for synthesis of α,α-disubstituted carbonyl compounds from carbonyl compounds with one-carbon homologation in only two synthetic steps.

Cross-coupling of nonstabilized aziridinylmagnesiums with alkylhalides catalyzed by Cu(I) iodide: a new synthesis of amines bearing a quaternary chiral center and an asymmetric synthesis of both enantiomers of the amines from one chiral starting material

Treatment of sulfinylaziridines, which were synthesized from 1-chloroalkyl p-tolyl sulfoxides and imines, with ethylmagnesium bromide gave nonstabilized aziridinylmagnesiums by a sulfoxide-magnesium exchange reaction. The cross-coupling of the aziridinylmagnesiums with various kinds of alkylhalides was realized in high yields by using Cu(I) iodide as a catalyst, and the reaction was found to be stereospecific. The coupling products were hydrogenated with Pd(OH) 2 in alcohol to give the amines bearing a quaternary chiral center in quantitative yields. Synthesis of both enantiomers of the amines bearing a quaternary chiral center was realized starting from optically active ( R)-chloromethyl p-tolyl sulfoxide in good overall yields with perfect asymmetric induction.

Favorskii Rearrangement and Carbon–Carbon Bond-Cleavage of α-Chloro-α-sulfonyl Ketones: A Synthesis of Carboxylic Acids and Their Derivatives from Aldehydes and Ketones

Abstract A method for synthesizing carboxylic acids and their derivatives from aldehydes and ketones via α-chloro-α-sulfonyl ketones is described. Acyclic α-chloro-α-sulfonyl ketones were synthesized from aldehydes and 1-chloroalkyl p-tolyl sulfoxides with carbon–carbon coupling in good overall yields. Cyclic α-chloro-α-sulfonyl ketones were synthesized from cyclic ketones in three steps in high overall yields. The Favorskii rearrangement of both acyclic- and cyclic α-chloro-α-sulfonyl ketones with sodium hydride in the presence of amine gave β-sulfonyl amides with skeletal rearrangement in good to excellent yield. Amides and α,β-unsaturated amides were synthesized from the β-sulfonyl amides. Treatment of the cyclic α-chloro-α-sulfonyl ketones with alkoxides and hydroxide gave carboxylic esters and acids with cleavage of the ring in good to excellent yields.

Recent Developments in Organic Synthesis with 1-Haloalkyl Aryl Sulfoxides

This account deals with recent developments in organic synthesis with 1-haloalkyl aryl sulfoxides, especially with 1-chloroalkyl aryl sulfoxides. 1-Chloroalkyl aryl sulfoxides are quite easily prepared from alkyl aryl sulfides. Sulfinyl carbanions and sulfinylated carbon radicals can easily be generated from 1-chloroalkyl aryl sulfoxides. The sulfinyl carbanions were added to carbonyl compounds to give the adducts, from which various kinds of new carbonyl compounds with carbon homologation were synthesized. Optically active 1-chloroalkyl p-tolyl sulfoxides were obtained from optically active (-)-chloromethyl p-tolyl sulfoxide. Asymmetric syntheses of epoxides, α-amino aldehydes, aziridines, α-hydroxy acids and their derivatives, and propargylic alcohols were realized starting from the optically active (-)-1-chloroalkyl p-tolyl sulfoxides. 1.Introduction 2.Synthesis of 1-Haloalkyl Aryl Sulfoxides 3.Organic Synthesis with 1-Haloalkyl Aryl Sulfoxides 4.Organic Synthesis with Sulfinyloxiranes 4.1.Reaction of Sulfinyloxiranes under Heating or with Lewis Acids 4.2.Reaction of Sulfinyloxiranes with Benzeneselenolate and Thiolates 4.3. Reaction of Sulfinyloxiranes with Amines, Cesium Acetate, and Metal Halides 4.4. Reaction of Sulfinyloxiranes with Alkylmetals 5.Asymmetric Synthesis with Optically Active (-)-1-Chloroalkyl p-Tolyl Sulfoxides 5.1. Preparation of Optically Active Sulfinyloxiranes and a Synthesis of Optically Active Epoxides, α-Amino Aldehydes, and Aziridines 5.2. Asymmetric Synthesis of Both Enantiomers of α-Hydroxy Acids, Esters, Amides, and Propargylic Alcohols 6. Conclusion

A novel method for generation of carbenoid from α-chloro sulfoxides: A new and versatile procedure for one-carbon homologation of carbonyl compounds to carbonyl compounds having an α-alkyl substituent

Addition of the carbanion of 1-chloroalkyl p-tolyl sulfoxides to carbonyl compound gave the adducts, which were treated with a base followed by t-butyllithium to afford one-carbon homologated carbonyl compounds having an alkyl group at the α-position, via the β-oxido carbenoids, in moderate to good yields.

1-Chloroalkyl p-tolyl sulfoxides as useful agents for homologation of carbonyl compounds: conversion of carbonyl compounds to .alpha.-hydroxy acids, esters, and amides and .alpha.,.alpha.'-dihydroxy ketones

One-carbon homologation of carbonyl compounds to α-hydroxy acids, esters, and amides by the use of 1-chloroalkyl p-tolyl sulfoxide as a hydroxycarbonyl anion equivalent is reported. Oxidation of the vinyl chlorides, the intermediates of the above-mentioned method, with osmium tetraoxide gives α,α'-dihydroxy ketones which are found in biologically active natural products such as cortisone and adriamycin

Nucleophilic Ring-Opening of Chlorooxiranes: A New Synthesis of α-Hydroxy α′-Substituted Ketones from Carbonyl Compounds and 1-Chloroalkyl p-Tolyl Sulfoxides

Abstract The addition of 1-chloroalkyl p-tolyl sulfoxides to carbonyl compounds gave adducts which were then converted to chlorooxiranes in two steps with good overall yields. The treatment of the chlorooxiranes with various nucleophiles gave α-hygroxy α′-substituted ketones or α-hydroxy ketones in good yields.

1-クロロアルキルアリルスルホキシドの化学 : カルボニル化合物の新規合成法の開拓と不斉合成への展開

This review deals with novel methods for a homologation of carbonyl compounds by using 1-chloroalkyl aryl sulfoxides as acyl anion equivalents. The products obtained from these methods are those of dialkyl ketones, aldehydes, α-substituted carbonyl compounds, vinyl-and divinyl ketones, 1-acylbutadienes, α, β-unsaturated carbonyl compounds, aldols, epoxides, allylic alcohols, (Z)-N-arylaziridines, and α-hydroxycarboxylic acids and their derivatives. Novel synthetic methods for cyclic ketones or new annulation procedures were achieved by using these new procedures. As the novel methods for asymmetric synthesis, a practical procedure for preparing optically pure 1-chloroalkyl p-tolyl sulfoxides was achieved. Optically active epoxides, (Z)-N-arylaziridines, α-amino aldehydes, and α-hydroxycarboxylic acids and their derivatives were synthesized from carbonyl compounds or imines and the optically active 1-chloroalkyl p-tolyl sulfoxides.

The practical procedure for a preparation of 1-chloroalkyl p-tolyl sulfoxides in high optically active form: A very short synthesis of optically active disparlure

A chlorination of optically active alkyl p-tolyl sulfoxides with N-chlorosuccinimide in dichloromethane in the presence of potassium carbonate afforded optically active 1-chloroalkyl p-tolyl sulfoxides in 87–94% ee (88–94% chemical yields). The optically active chloroalkyl sulfoxide was applied to a synthesis of optically active (+)-disparlure.

Stereospecific desulfinylation of sulfinylaziridines with ethylmagnesium bromide: A novel synthesis of (Z)-N-arylaziridines

A novel synthesis of (Z)-N-arylaziridines was realized by the stereospecific desulfinylation of (E)-(N-aryl)sulfinylaziridines which were synthesized from 1-chloroalkyl p-tolyl sulfoxides and N-arylimines in high yields.