Synthesis of α-Benzotriazole Selenides and Tellurides Promoted by Samarium Diiodide

1-(Benzotriazol-1-yl) unsymmetrical diorganyl selenides and tellurides were synthesized via replacement of chlorine atom in 1-(benzotriazo-l-yl)-l-chloromethane with selenolate and tellurolate anions promoted by SmI₂.     

Temperature-Controlled Stereodivergent Synthesis of 2,2′-Biflavanones Promoted by Samarium Diiodide

In this work, the first example of a radical stereodivergent reaction directed towards the stereoselective synthesis of both (R*,R*)- and (R*,S*)-2,2′-biflavanones promoted by samarium diiodide is reported. Control experiments showed that the selectivity of this reaction was exclusively controlled by the temperature. It was possible to generate a variety of 2,2′-biflavanones bearing different substitution patterns at the aromatic ring in good-to-quantitative yields, being both stereoisomers of the desired compounds obtained with total or high control of selectivity. A mechanism that explains both the generation of the corresponding 2,2′-biflavanones and the selectivity is also discussed. The structure and stereochemistry determination of each isomer was unequivocally elucidated by single-crystal X-ray diffraction experiments.     

Synthesis of 1,3-Diketones by Reaction of α-Haloketones with Acyl Cyanides Promoted by Samarium Diiodide

α-Haloketones reacted with acyl cyanides to form 1,3-diketones in the presence of samarium diiodide. The reaction was assumed to proceed via a mechanism involving samarium enolates formed in situ from α-haloketones.     

Cyclodimerization of α, β-Unsaturated Ketones Promoted by Samarium Diiodide

Samarium (II) iodide has been successfully utilized as a strong one-electron transfer reducing agent for the cyclodimerization of α, β-unsaturated ketones. The absence of any alcohol as proton source is essential. The reaction is regioselective over the competitive carbon-carbon double bond reduction and stereocontrolled. The configuration of the cyclodimerization products, has been confirmed by X-ray analysis.     

Synthesis of Aminomethyl Arylsulfides via Novel Synthetic Auxiliary Benzotriazole Promoted by Samarium Diiodide

Benzotriazolemethodologyhasalreadycomealongway,butinthelastdecadebenzotriazoleisanexcellentsyntheticauxiliaryinmanyusefulsynthetictransformationsl-5.Becausebenzotriazolateanionisagoodleavinggroup,itmaybeusedinplaceofahalogeninmanyreactions.Theuseofbenzotriazoleasasyntheticauxiliaryhasanumberofsignificantadvantages.Forexample,itisreadilyavailableandquitecheap;itisacidicwithapKaofabout8,whichenableseasyseparationandrecovery.Manytypesofcompoundshavebeensynthesizedviabenzotriazoleauxifiary>.Samar…     

Facile Synthesis of Amidines via Intermolecular Reductive Coupling of Nitriles with Azobenzene Promoted by Samarium Diiodide

SinceintroducedbyKaganandhisgroups',Sml,hasbeenextensivelyinvestigatedasamild,neutral,selectiveandversatilesingIeelectrontransferreductantinsyntheticchemistry=.Suchas,Barbierreactions,Reformatskyreactions,pinacolcouplingandketone-oIefinreductivehavebeenreportedusingSmI,asreagent.Thereactivitiesofvariousnitrogenfunctionalgroups(imine,oxime,nitro,azo,cyano)towardsSmI,havealsobeenexamined.Recently,ourgrouphasreportedtheintermolecularreductivecouplingofnitrogroupswithcyanogroupsinducedbySml='.…     

Synthesis of α-Amino Unsymmetrical Diorganyl Selenides via Novel Synthetic Auxiliary Benzotriazole Promoted by Samarium Dhodide

α -Amino unsymmetrical diorganyl selenides are synthesized through nucleophilic substitution of a benzotriazolate anion by selenolates promoted by samarium diiodide.     

β-Diketone Synthesis by Reaction of α-Haloketones with Acid Chlorides or Acid Anhydrides Promoted by Samarium Triiodide

Promoted by SmI₃, α-haloketones were reacted with acid chlorides or acid anhydrides and β-diketones were synthesized via intermediate samarium enolates.     

Reductive Cleavage of S-S Bond by Samarium Diiodide: Synthesis of β-Thioesters and β-Thionitriles

Theuseofsamariumdiiodideasastrongone-electrontransferreducingandcouplingreagentinorganicsynthesishasgainedincreasingpopularity,especiallyinthepasttenyears1OurpreviousworkonsomedeoxygenationandsomereductivecleavageofSe-SeorTe-TebondwithSmI2wasrepel'te...     

Preparation of α-Halovinyl Sulfides by Eliminative Deoxygenation of α-Halosulfoxides

Abstract

Vinyl sulfides are useful synthetic intermediates¹ which have received increasing attention recently both as masked carbonyl moieties² and in carbon-carbon bond forming reactions.³ With regard to the latter, vinyl sulfide derivatives which are substituted in the α-position with halogen, tin, selenium, etc., are particularly useful due to the ready formation of anions upon treatment with a variety of organometallic reagents.^{3 d ? 1} We report here that synthetically useful halovinyl sulfides can be produced in high yield by the eliminative deoxygenation of the corresponding α-halosulfoxides induced by electrophilic silicon reagents.     

A New Approach to 2,3-Dihydro-1H-1,5-Benzodiazepines from the Reaction of o-Nitrophenylazide with α,β-Unsaturated Ketones Promoted by Samarium Diiodide

Applications of samarium diiodide as a mild, neutral, selective and versatile single-electron transfer reducing and coupling reagent in organic synthesis have grown significantly in the last decade1. It is well known that both nitro compounds2a and azide compounds2b can be easily reduced by SmI2 to the corresponding amines. Little attention has been given to the intermediates derived from nitro or azide groups by treatment of SmI2, which may lead to reactions difficult to accomplish by other …     

Samarium(Ⅱ) Iodide Promoted Synthesis of 1-ethoxycarbonylmethyl-2-hydrofullerene

The ethyl analog of the above compound has been reported before by severalgroupsg- I 1. For example Komatsu and coworkers synthesized C60(H)(CHZCOOEt) by aReformatsky-type of reaction, treating ethyl bromoacetate and zinc with C60 in avibrating mill without any solventg. Besides the main product C60(H)(CHZCOOEt),three other byproducts were also isolated including a l,4-dihydrofullerene derivativeC60(CHZCOOEt)2. The spectroscopic data of the present product confirm its structure asd…     

The Reductive Addition Reaction of Substituted 2-Chloromethyl-1, 3, 4-oxadiazole to Aldehydes and Ketones Promoted by Samarium Diiodide

1-（β-Hydroxyalkyl）-l,3,4-oxadiazole derivatives were synthesized via reductive addition reactions of 2-chloromethyl-l,3,4-oxadiazole with carbonyl compounds under mild conditions promoted by SmI2.     

Synthesis of Allyl-Type Selenides and α-Selenoesters in Aqueous Media Promoted by Cadmium

Promoted by metallic cadmium which was produced by reduction of CdCl₂ H₂O with samarium in situ, allyl bromide and α-bromocarboxylates react with diorgano diselenides in aqueous solutions to give allylic-type selenides and α-selenocarboxylates in moderate to good yields.     

Synthesis of α-Acetylenic Aldehydes from 2-Acetylenic Phenyl Sulfides

Monochlorination at the 1 position, with sulfuryl chloride, followed by hydrolysis converted 2- acetylenic phenyl sulfides into 2-acetylenic aldehydes.     

Synthesis of α-Phenylthio Alkyl Nitriles from α-Chloro Alkyl Phenyl Sulfides

α-Chloro Alkyl Phenyl Sulfides are converted with Trimethylsilyl Cyanide, in a reaction catalyzed by SnCl₄, into α-Phenylthio Alkyl Nitriles.     

Synthesis of the Cyclopentenylamine Derivatives Promoted by SmI2

The intermolecular reductive coupling of 1,1-diary1-2,2-drcyanoethylenes with cinnamic esters promoted by samarium( Ⅱ）iodide was studied.Functionalized cyclopentenylamine derivatives were prepared in good yields under neutral and mild conditions.     

Michael Additions of Activated Methylene Compounds to α,β-Unsaturated Esters Promoted by Samarium (Ⅲ) Iodide

IntheIastdecadestheapplicationsofsamariumreagentsinorganicsynthesishavebeenrapidlyincreasedl-6.CatalyzedbySm(OTO,benzyIaminecanaddtoethylcrotonatetoformD-aminoesters=;attheaidofSm(OTfl,ands-BuLimethyliodidehasbeenaddedtocarbonylgroupofacetophenone';WehavereportedthatpromotedbySml,a-haloketonescanreactwithaldehydestogiveQ,6=unsaturatedketones4.VeryrecentlywefoundthatD-diketonescanbesynthesizedviareactionofa-haloketoneswithacidchloridesoracidanhydridesattheaidofSmI=orSmI,'.Wealsoreported…     

Silver Fluoroborate Promoted Sulfur Alkylation of β-Silyl Ethyl Sulfides. Selective Synthesis of β-Thioglycosides

Silver (I) activation of α-glucosyl bromide in the presence of 2-trimethylsilylethyl sulfides as sulfur nucleophiles selectively provides β-thioglycosides.     

Synthesis of α-Selenoesters By Reactions of α-Bromoesters With Diselenides Promoted By Metallic Tin

TherehavebeenlargeqUanitiesofexamplesaboutmetallictinaPplicationinorgbocsynhesis.1ButitwasmainlyrestriCtedtothepreparationoforganotaouscomPOundspreviously.Notmanyexampleswereboownaboutsynthehcreachonsusingmetallictindirectly.'RecentlydeveloPedaqueousorganometallicreactionincreasedtheexamplesofdirectapplicationoftinmetal,butthetyPeofthereactionseemstobesomewhatlimited.IthasbeenusedmainlyinallylationandpropargylationofcarbonylcomPOunds.'Herewewishtoreportthata-bromoesterscanreactwithdiseleni…