ALLYLATION OF AROMATIC AMINES VIA ALLYLDIALKYLTELLURONIUM SALTS

Allyldialkyltelluronium bromides were treated with aromatic amines in 1,2-dichloroethane,readily giving allyl aryl amines in excel- lent yields.This method provides a convenient one-pot reaction for the synthesis of allylic amines.

In(OTf)_3 catalyzed allylation reaction of imines with tetraallyltin

In the presence of catalytic amount of In（OTf）3 （10 mol%）, a series of aldimines reacted with tetraallyltin in a 2：1 molar ratio to afford the corresponding homoallylic amines in good yields. The good atom efficiency was achieved under mild reaction conditions and a new protocol （allyl）4Sn/In（OTf）3 for simple imines was developed.

REGIOSELECTIVE ALLYLATION OF THE TERMINAL EPOXIDES BY ALLYL BROMIDE AND METALLIC ZINC OR TIN

Allylation of terminal epoxides(1)to give the homoallylic alcohols(2)and bishomoallylic alcohols(3)can be carried out successfully by allyl bromide and metallic zinc or tin.The effect of substituents on epoxides was studied.

Tin Mediated Allylation of Aldimines with Allyl Bromide

Aldimines are allylated with allyl bromide and tin powder in tetrahydrofuran to give homoallylamines in the presence of chlorotrimethylsilane.

Simple and Clean Synthesis: Tin-mediated Allylation of Carbonyl Compounds in Water

Tin mediated allylation of aldehydes or ketones in distilled water gives rise to the corresponding homoallyl alcohols in high yield without assistance such as heat, supersonic and acidic media.

Ligand-Controlled Palladium-Catalyzed Regiodivergent Defluorinative Allylation of gem-Difluorocyclopropanes viaσ-Bond Activation

Monofluoroalkenes are important and versatile privileged components in pharmacologically relevant molecules.Here,we report a method for the selective construction of these compounds in a diversity-oriented fashion through regiodivergent cross-coupling of gem-difluorocyclopropanes with allylboronates by employing a palladium catalyst with two different ligands,in which gem-difluorocyclopropanes were used as allyl electrophiles by C—C and C—F bond activation.In the presence of 2-biphenylyl(diphenyl)phosphine as ligand,the linear-selective allyl–allyl bond formation is highly obtained,while utilizing the sterically hindered BrettPhos(dicyclohexyl[3,6-dimethoxy-2',4',6'-tris(1-methylethyl)[1,1'-biphenyl]-2-yl]phosphine)as the ligand favors the generation of the branched-selective product.Experimental and computational studies investigated the key steps of the cross-coupling reactions,revealing the origin of the ligand-controlled regiodivergence.

Asymmetric Catalytic α-Selective Allylation of Ketones with Allyltrifluoroborates Using Dual-Functional Chiral In^(Ⅲ)/N,N'-Dioxide Complex

Comprehensive Summary Asymmetric catalytic allylation of halo-substituted ketones and ketoesters was accomplished to yield a number of homoallylic tertiary alcohols in excellent reactivity and enantioselectivity.In the presence of chiral In^(Ⅲ)/N,N-dioxide catalyst,unusual α-selective allylation ofγ-substituted potassium allyltrifluoroborates to ketones was demonstrated.The control experiments and DFT calculation reveal that chiral In^(Ⅲ)/N,N'-dioxide catalyst plays dual-tasking roles:the formation of allylindium species via transmetalation and Lewis acid activation.Apossiblereaction pathwaywas provided tounderstandα-selectivity overy-selectivity.

Cobalt-Catalyzed C-H Allylation of Arenes with Allylic Amines

[Cp^(*)Co(CO)l_(2)]effectively catalyzes pyridyl-directed C-H allylation of arenes with allylic amines in the presence of AgOAc and CF_(3)COOAg.The reaction features ortho-position monoallylation of 2-pyridylarenes,giving the allylated arenes in moderate to high yields.A range of functional groups including OMe,Me,Ph,F,Cl,Br,CF_(3),C(0)Me,COOEt,and COOH groups are tolerated.Pyrim-idyl-directed C-H allylation of arenes were also performed under the same conditions.Reaction of 2-phenylpyrimidine,2-(4-methoxyphenyl)pyrimidine/and 2-(3-fluorophenyl)pyrimidine leads to a mixture of ortho-position mono-and bisallylation products.Reaction of other 2-(substituted aryl)pyrimidines resulted in ortho-position monoallylation products.

Asymmetric Synthesis of Novel Axially Chiral 2,2＇-Bipyridine N,N＇-Dioxides Bearing α-Amino Acid Residues and Their Applications in Enantioselective Allylation of Aromatic Aldehydes with Allyltrichlorosilane

A series of novel axially chiral 2,2＇-bipyridine N,N＇-dioxides bearing C1 or C2-symmetry have been synthesized by the use of enantiopure a-amino acids as chiral sources. The absolute stereochemistry of the axial chirality of these organocatalysts has been clearly assigned by means of CD measurements together with literature protocols. The reactivities and enantioselectivities of these organocatalysts have been examined in the reactions of aromatic aldehydes with allyltrichlorosilane, thus providing the desired products with moderate yields and enantioselectivies.

Allylation and alkylation of oxindoleketimines via imine umpolung strategy

When treated with an alkoxide base like t-BuOK in aprotic solvent,N-di phenyl methyl imino oxindoles,made conveniently through condensation of corresponding isatins with N-di phenyl methyl amine,are deprotonated to form azaallyl anions.Allylation and alkylation of this type of intermediates proceed smoothly with diverse C-electrophiles.Acidic work up finishes 3-amino-3-allyl/alkyl oxindoles.The overall transformation equals to an umpolung process at the C3 of isatins.

Palladium-catalyzed base-and solvent-controlled chemoselective allylation of amino acids with allylic carbonates

The utilization of readily available amino acids,which is not only an oxygen nucleophile but also a nitrogen nucleophile,in palladium-catalyzed allylic substitution is realized under mild conditions.The chemoselectivity and multiple allylation are controlled by adjusting the reaction conditions.This represents the first example of this convenient access to valuable N,O-diallylated amino acids.Under the title conditions,a range of amino acids(α-,β-,γ-)and dipeptides can be readily converted in to the corresponding allylic products with excellent yields(67 examples,up to 99%yield)as well as good functional group tolerance.

SnCl_2/Cu-Mediated Carbonyl Allylation Reaction in Water: Scope, Selectivity and Mechanism

Copper was found to be able to promote the SnCl2-mediated carbonyl allylation reactions in water, giving the corresponding homoallylic alcohol products in very high yields. Detailed studies showed that the reaction could be applied to a variety of carbonyl compounds including those with hydroxyl, amino and nitro groups. It was also found that this reaction showed good regioselectivities for some substrates. Furthermore, carefully controled ex-periments and in situ NMR measurements provided important insights into the mechanism of the newly developed reaction.

Synthesis of Chiral Sulfoxides and Application in Enantioselective Allylation of Aldehydes with Allyltrichlorosilane

1 Results The enantioselective addition of allylic organometallic reagents to aldehydes is a fundamental tool in organic synthesis.The high degree of both diastereo-and enantioselectivity gives the possibility to obtain a wide series of homoallylic alcohols,versatile intermediates in a great number of synthesis[1]. One of the most successful approaches is related to the discovery that organocatalytic activation of the nucleophilic allyltrichlorosilanes by means of neutral Lewis bases,such as formamides,...

Three-Component Barbier Allylation-Friedel-Crafts Alkylation Promoted by BuPyCI/SnCI2·2H2O： Application to the Synthesis of 4-（Substituted phenyl）chromans

Barbier allylation and Friedel-Crafts alkylation of （un）substituted benzaldehydes, allylbromide and phenols can be combined in a one-pot process in ionic liquid （BuPyC1/SnC12·2H2O） to directly synthesize 4-（2-hydroxyphenyl）- 4-[（un）substituted phenyl]but-1-ene compounds, which were applied to the synthesis of 4-（substituted phenyl）- chromans through intramolecular cyclization reactions.

Chemoselective Benzylation and Allylation of 4-Nitrobenzaldehyde Promoted by Phase Transfer Catalyst and Metal in Aqueous Media

The benzylation and allylation of 4-nitrobenzaldehyde (1) could be controlled chemoselectively by using different phase transfer catalyst (FTC) and different metal catalysts. And then, benzylation and allylation of 1 with various organic halides has been realized in high yields in aqueous media.

Synthesis of Aminophosphine Ligands with Binaphthyl Backbones for Silver(I)-catalyzed Enantioselective Allylation of Benzaldehyde

A series of aminophosphine ligands was synthesized from 2-amino-2′-hydroxy-1,1′-binaphthyl (NOBIN). Their asymmetric induction efficiency was examined for silver(I) catalyzed enantioselective allylation reaction of benzaldehyde with allyltributyltin. Under the optimized reaction conditions, quantitative yield as well as moderate ee value (54.5% ee) of product was achieved by the catalysis with silver(I)/3 complex. The effects of the binaphthyl backbone and the substitutes situated at chelating N, P atoms on enantioselectivity of the reaction were also discussed.

Design and Application of Indole-Based Allylic Donors for Pd-Catalyzed Decarboxylative Allylation Reactions

of main observation and conclusion A new class of indole-based allylic donors have been designed and developed for palladium-catalyzed decarboxylative allylations.In addition,the first application of these indole-based allylic donors in palladium-catalyzed decarboxylative[3+2]cydoaddition and allylic amination has been achieved by reacting with isocyanates and sulfonyl amines,respectively.This approach represents the first design of indole-based allylic donors,which is helpful for settling the challenge of designing and developing new class of heterocycle-based allylic donors for Pd-catalyzed decarboxylative allylation reactions.Moreover,the application of this new class of allylic donors in cycloadditions and substitutions will add new contents to the research field of decarboxylative allylation.

Palladium-catalyzed allylation of active methylene compounds with allyl perfluoroalkanoates under neutral conditions

Palladium-catalyzed allylation of carbonucleophiles has been widely used for carbon-carbon bond formation.Among the allylic compounds studied,allylic acetates were mostwidely used as precursors of(π-allyl)palladium intermediates.However,bases such as NaHmust be used to generate anions in this reaction.Recently,research on carrying out the palla-.

Access to chiral homoallylic vicinal diols from carbonyl allylation of aldehydes with allyl ethers via palladium-catalyzed allylic C-H borylation

Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.