Chloromethyl Phenyl Sulfoxide Research Articles

On the nature of the chain-extending species in organolithium initiated stereospecific reagent-controlled homologation reactions using α-chloroalkyl aryl sulfoxides

The reaction of an organolithium with an α-chloroalkyl aryl sulfoxide ostensibly generates an α-chloroalkyllithium by sulfoxide–lithium exchange, but the actual identity of the chain-extending species in chlorosulfoxide-based StReCH reactions is not certain. To explore this issue, racemic 2-cyclohexyl (4R∗,5R∗)-4,5-diphenyl-1,3,2-dioxaborolane was homologated by treatment with scalemic (S)-chloromethyl phenyl sulfoxide and n-BuLi (THF, −78°C). The reaction proceeded without a detectable level of kinetic resolution, a finding consistent with chloromethyllithium being the active chain-extending species rather than a chiral sulfurane intermediate.

ChemInform Abstract: A New Method for the Synthesis of α-Thio Aldehydes and Alcohols from Aldehydes with One-Carbon Elongation.

Abstract A two-step and high-yield method for the synthesis of α-thio aldehydes from aldehydes with one-carbon elongation is realized by using chloromethyl phenyl sulfoxide as a one-carbon homologating agent. The α-thio aldehydes are easily converted to desulfurized alcohols with Bu3SnH and AIBN in refluxing benzene in good yield.

Development of New Synthetic Methods with Aryl 1‐Chlorovinyl Sulfoxides

AbstractFor Abstract see ChemInform Abstract in Full Text.

Development of new synthetic methods with aryl 1-chlorovinyl sulfoxides.

Aryl 1-chlorovinyl sulfoxides were easily synthesized from ketones and aldehydes with aryl chloromethyl sulfoxide in three-steps with high overall yields. Low-temperature treatment of the aryl 1-chlorovinyl sulfoxides with alkyllithium or a Grignard reagent gave alkylidene carbenoids via a sulfoxide-metal exchange reaction. From the alkylidene carbenoids, acetylenic compounds, tetra-substituted olefins, and allenes were synthesized. Enolization of alpha-chloro alpha-sulfinyl ketones, which were synthesized from methyl esters and chloromethyl phenyl sulfoxide, is another method for the generation of aryl 1-chloroalkyl sulfoxides. Treatment of 1-chlorovinyl phenyl sulfoxides so generated with t-BuLi followed by some nucleophiles having an acidic hydrogen gave one-carbon elongated carboxylic acids and their derivatives. Conjugate addition of some carbanions with 1-chlorovinyl p-tolyl sulfoxides was found to have taken place. For example, reaction of 1-chlorovinyl p-tolyl sulfoxides with cyanomethyllithium gave high yields of cyclic enaminonitriles. Acidic treatment of the enaminonitriles afforded good yields of 4,4-disubstituted 2-cyclopentenones. By using unsymmetrical ketones and optically pure chloromethyl p-tolyl sulfoxide, this procedure suggests a good method for an asymmetric synthesis of optically pure 4,4-disubstituted 2-cyclopentenones. This method achieved an asymmetric total synthesis of (+)-alpha-cuparenone starting from methyl 4-methylphenyl ketone and (R)-(-)-chloromethyl p-tolyl sulfoxide. A novel synthesis of 2,4,4-trisubstituted 2-cyclopentenones is also successful using cyanomethyllithium and its homologues. Conjugate addition of the lithium enolate of tert-butyl acetate and its homologues gave high yields of the adduct, 3,3-disubstituted esters. Synthesis of various kinds of carboxylic acids and their derivatives and lactones was realized from the adducts.

A new synthesis of β,γ-alkenyl carboxylic acids from α,β-alkenyl carboxylic acid chlorides and α,β-alkenyl aldehydes with one-carbon elongation

Reaction of the lithium α-sulfinyl carbanion of chloromethyl phenyl sulfoxide with α,β-alkenyl carboxylic acid chlorides gave γ,δ-alkenyl α-chloro-β-keto sulfoxides in variable yields. The keto sulfoxides were also synthesized from α,β-alkenyl aldehydes in two steps in good overall yields: addition of the lithium α-sulfinyl carbanion of chloromethyl phenyl sulfoxide to α,β-alkenyl aldehydes followed by oxidation of the adducts with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone or Dess–Martin periodinane. These products were treated in sequence with potassium hydride, tert-butyllithium, and 5% aqueous sodium hydroxide, in one flask to give β,γ-alkenyl carboxylic acids with one-carbon elongation in good yields. The procedure offers a new method for synthesizing β,γ-alkenyl carboxylic acids from α,β-alkenyl carboxylic acid chlorides and α,β-alkenyl aldehydes with one-carbon elongation.

A new method for the synthesis of α-thio aldehydes and alcohols from aldehydes with one-carbon elongation

A two-step and high-yield method for the synthesis of α-thio aldehydes from aldehydes with one-carbon elongation is realized by using chloromethyl phenyl sulfoxide as a one-carbon homologating agent. The α-thio aldehydes are easily converted to desulfurized alcohols with Bu 3SnH and AIBN in refluxing benzene in good yield.

One-carbon ring enlargement of lactones

Two-step or three-step one-carbon ring enlargement of lactones is realized from lactones and chloromethyl phenyl sulfoxide via a rearrangement of alkylidene carbenoid followed by intramolecular cyclization of the ω-hydroxyalkyl ketene intermediate or via a 2-pyridinethiol ester.

Ligand exchange reaction of sulfoxides in organic synthesis: A versatile procedure for one-carbon homologation of methylesters to esters, thioesters, carboxylic acids and amides

Abstract A novel two-step procedure for one-carbon homologation of methylesters to esters, thioesters, carboxylic acids and amides is described. Methylesters are reacted with lithium carbanion of chloromethyl phenyl sulfoxide to give α-chloro α-sulfinyl ketones in 70 to 90% yields. Potassium enolate of the α-chloro α-sulfinyl ketone was treated with tert-butyllithium at −78 °C to give alkynolate via alkylidene carbenoid. This intermediate was treated with alcohols, thioles, 5% aqueous NaOH, and amine hydrochlorides to afford one-carbon homologated esters, thioesters, carboxylic acids and amides, respectively, in good to excellent yields.

A novel stereoselective synthesis of cis-2-fluorocyclopropane-1-carboxylic acid

A novel method consisting four-step from tert-butyl acrylate ( 4) and chloromethyl phenyl sulfoxide ( 5) for preparing cis-2-fluorocyclopropane-1-carboxylic acid ( cis- 3 ) was elaborated. The method involves initial formation of the cis-2-phenylsulfinylcyclopropanecarboxylate ( cis- 6 ), fluorination by molecular fluorine to trans- 7 , reductive desulfonylation to the ester ( cis- 9 ) and acid-catalyzed hydrolysis to the final product ( cis- 3 ).

Ligand exchange reaction of sulfoxides in organic synthesis: A new synthesis of α-chloroketones from carbonyl compounds with one-carbon homologation

A new procedure for one-carbon homologation of carbonyl compounds to α-chloroketones is described. Addition of the carbanion of dichloromethyl phenyl sulfoxide with ketones and aldehydes gave the adducts, chloro alcohols, in good yields. Treatment of the chloro alcohols with EtMgBr or lithium diisopropylamide gave one-carbon homologated α-chloroketones via β-oxido carbenoid rearrangement in moderate to good yields. One-carbon homologation of esters to α-chloroketones was realized via the ligand exchange reaction of the sulfinyl group of α-chloro α-sulfinyl ketones, which were synthesized from methyl esters and chloromethyl phenyl sulfoxide, with EtMgBr.

Generation of the α-Sulfinyl Carbenoid from α-Chloro Sulfoxides: A New Method for One-Carbon Homologation of Ketones to α-Sulfinyl Ketones

Abstract Treatment of 1-chloroalkyl phenyl sulfoxides with a base gave carbenoids rather than free carbenes. The carbenoids were successfully used in a new method for homologation of ketones to α-sulfinyl ketones. Treatment of the carbanion of chloromethyl phenyl sulfoxide with ketones gave the adducts, α-chloro β-hydroxy sulfoxides, in nearly quantitative yields. The adducts were treated with excess lithium diisopropylamide to give one-carbon homologated α-sulfinyl ketones via α-sulfinyl β-oxido carbenoids in moderate to good yields. This type of reaction was found not to occur with the corresponding sulfones.

Ligand exchange reaction of sulfoxides in organic synthesis: a new method for one-carbon homologation of esters to carboxylic acids and esters via α-chloro α-sulfinyl ketones

Reaction of the Carbanion of chloromethyl phenyl sulfoxide with esters gave α-chloro α-sulfinyl ketones, which were treated with KH followed by t-BuLi to afford one-carbon homologated acids and esters in good to excellent yields.

α-Sulfinyl carbenoid: One-carbon homologation of ketones to α-sulfinyl ketones using chloromethyl phenyl sulfoxide

Addition of the carbanion of chloromethyl phenyl sulfoxide to ketones gave the adducts, which were treated with lithium diisopropylamide to afford one-carbon homologated α-sulfinyl ketones via α-sulfinyl carbenoids in moderate to high yields.

7187. rf diode sputtering: JS Logan, Thin Solid Films, 188, 1990, 307–321

Addition of the carbanion of chloromethyl phenyl sulfoxide to ketones gave the adducts, which were treated with lithium diisopropylamide to afford one-carbon homologated α-sulfinyl ketones via α-sulfinyl carbenoids in moderate to high yields.

α,β-Epoxy Sulfoxides as Useful Intermediates in Organic Synthesis. X. An Improved Synthesis of α,β-Unsaturated Carbonyl Compounds from Carbonyl Compounds with Carbon Homologation through α,β-Epoxy Sulfoxides

Abstract Treatment of the α,β-epoxy sulfoxides derived from ketones and chloromethyl phenyl sulfoxide or 1-chloroalkyl phenyl sulfoxides with lithium perchlorate in the presence of tributylphosphine oxide in toluene at 110 °C for about 1–3 h gave α,β-unsaturated aldehydes or α,β-unsaturated ketones in high yields. In contrast to these results, the α,β-epoxy sulfoxides derived from aldehydes did not give the desired α,β-unsaturated ketones. In this case, a sequential treatment of the α,β-epoxy sulfoxides with benzenethiolate and m-chloroperbenzoic acid afforded α-phenylsulfinylated ketones, which were heated in toluene at 110 °C to give the desired enones in good overall yields. The oxidation of the α,β-unsaturated aldehydes obtained by this method gave α,β-unsaturated carboxylic acids in high yields. These procedures afforded a new method for the synthesis of α,β-unsaturated carbonyl compounds, including α,β-unsaturated esters, from carbonyl compounds with carbon homologation.

α,β-Epoxy Sulfoxides as Useful Intermediates in Organic Synthesis. III. A Novel Synthesis of α-Amino Ketones and α-Amino Aldehydes by Aminolysis of α,β-Epoxy Sulfoxides

Abstract Aminolysis of α,β-epoxy sulfoxides, easily prepared from 1-chloroalkyl phenyl sulfoxides or chloromethyl phenyl sulfoxide and carbonyl compounds, with alkyl- or arylamines afforded α-amino ketones or α-amino aldehydes in good yields. Treatment of thus obtained α-arylamino ketones with weak Lewis acid led to 2,3-disubstituted indoles.

ChemInform Abstract: SYNTHESIS OF α‐AMINO KETONES FROM α,β‐EPOXY SULFOXIDES

AbstractDie Epoxide (I) reagieren mit den Aminen (II) zu den α‐Aminoketonen (III).

SYNTHESIS OF α-AMINO KETONES FROM α,β-EPOXY SULFOXIDES

Abstract Various kinds of α-amino ketones and α-arylamino ketones are synthesized in good yields by aminolysis of α,β-epoxy sulfoxides which are easily prepared from alkylated chloromethyl phenyl sulfoxide and carbonyl compounds.

Alkylation and pyrolysis of chloromethyl phenyl sulfoxide: A simple synthesis of vinyl clorides

Alkylation and pyrolysis of chloromethyl phenyl sulfoxide: A simple synthesis of vinyl clorides

Stereospecific hydroxyalkylation of chloromethyl phenyl sulfoxide

Stereospecific hydroxyalkylation of chloromethyl phenyl sulfoxide