Direct Allylation Research Articles

ChemInform Abstract: The Nickel(II)‐Catalyzed Direct Benzylation, Allylation, Alkylation, and Methylation of C—H Bonds in Aromatic Amides Containing an 8‐Aminoquinoline Moiety as the Directing Group.

AbstractThe nickel(II)‐catalyzed ortho‐alkylation of aromatic amides containing an 8‐aminoquinoline moiety as directing group is described.

ChemInform Abstract: Mild Rh(III)‐Catalyzed C7‐Allylation of Indolines with Allylic Carbonates.

The rhodium(III)-catalyzed direct allylation of indolines with allylic carbonates at room temperature is described. These transformations provide the facile and efficient construction of C7-allylated indolic scaffold.

ChemInform Abstract: Highly Efficient Direct Allylation of Oxindoles with Simple Allylic Alcohols Enabled by Palladium/Broensted Acid Catalysis.

AbstractPreliminary experiments towards an asymmetric allylation of (Ia) with (II) using chiral mono or diphosphine ligands furnish (IIIa) with up to 17% enantiomeric excess only.

ChemInform Abstract: Direct Allylation of Aromatic and α,β‐Unsaturated Carboxamides under Ruthenium Catalysis.

AbstractOther amide directing groups such as diethyl, methyl, dimethyl, or morpholinyl amido groups deliver the corresponding products with lower yields and lower regioselectivity than the pyrrolidinyl group.

Mild Rh(III)-catalyzed C7-allylation of indolines with allylic carbonates.

The rhodium(III)-catalyzed direct allylation of indolines with allylic carbonates at room temperature is described. These transformations provide the facile and efficient construction of C7-allylated indolic scaffold.

The Nickel(II)-Catalyzed Direct Benzylation, Allylation, Alkylation, and Methylation of C–H Bonds in Aromatic Amides Containing an 8-Aminoquinoline Moiety as the Directing Group

Abstract Direct alkylation via the cleavage of the ortho C–H bonds by a nickel-catalyzed reaction of aromatic amides containing an 8-aminoquinoline moiety as the directing group with alkyl halides is reported. Various alkyl halides, including benzyl, allyl, alkyl, and methyl halides (or pseudo halides) participate as electrophilic coupling partners. The reaction shows a high functional group compatibility. The reaction proceeds in a highly regioselective manner at the less hindered C–H bonds in the reaction of meta-substituted aromatic amides, irrespective of the electronic nature of the substituent. The mechanism responsible for the C–H alkylation reaction is discussed based on the results obtained in a variety of mechanistic experiments.

ChemInform Abstract: Stereocontrol in Synthesis of Homoallylic Amines. Syn Selective Direct Allylation of Hydrazones with Allylboronic Acids.

AbstractUnless otherwise mentioned the products are isolated as single diastereomers.

ChemInform Abstract: Direct Allylation of in situ Generated Aldehyde Acyl Anions by Synergistic NHC and Palladium Catalysis.

AbstractStarting from easily accessible allylic carbonates and aldehydes, an efficient access to β,γ‐unsaturated ketones under mild reaction conditions is provided.

Mild rhodium(III)-catalyzed C-H allylation with 4-vinyl-1,3-dioxolan-2-ones: direct and stereoselective synthesis of (E)-allylic alcohols.

A rhodium(III)-catalyzed C-H direct allylation reaction with 4-vinyl-1,3-dioxolan-2-ones has been developed. The reaction provides a facile and stereoselective access to substituted-(E)-allylic alcohols under mild and redox-neutral reaction conditions. Olefinic C-H activation is applicable, giving multifunctionalized skipped dienes in good yields. Minimal double-bond migration was observed.

Lewis‐Acid‐Catalyzed Direct Allylation of Electron‐Poor N‐Heterocyclic Amides through an Amide‐Aldehyde‐Alkene Condensation

AbstractWe report a general protocol for the direct N‐allylation of electron‐poor N‐heterocyclic amides and sulfonamides via an amide‐aldehyde‐alkene condensation reaction catalyzed by a Lewis acid. This process has a broad substrate scope with respect to N‐heterocyclic amides including carbamates, carboxamides, and N‐methylsulfonamides, and provides efficient access to a variety of allylamine derivatives in good yield with high regioselectivity. The utility of this method was also demonstrated by the rapid synthesis of Naftifine from N‐methyl‐1‐naphthamide, paraformaldehyde, and styrene in one‐pot.

ChemInform Abstract: Direct Allylation of Alcohols Using Allyltrimethylsilane and a Move Towards an Economical and Ecological Protocol for C—C Bond Formation

AbstractReview: 90 refs.

Highly Efficient Direct Allylation of Oxindoles with Simple Allylic Alcohols Enabled by Palladium/Brønsted Acid Catalysis

A highly efficient and practical direct allylic alkylation of oxindoles with simple allylic alcohols cocatalyzed by Pd(OAc)₂/Ph₃P and PhCO₂H under mild conditions has been developed, which streamlines the installation of an all-carbon quaternary allylic center at the oxindole 3-position. Enantioselective allylic alkylation has also been realized with the product in almost quantitative yield and 17% enantiomeric excess. Mechanistically, ESI analysis indicates that a palladium(0) species and π-allyl-Pd(PPh₃)₂ cation were involved.

Stereocontrol in synthesis of homoallylic amines. Syn selective direct allylation of hydrazones with allylboronic acids.

Allylboronic acids directly react with acyl hydrazones, affording homoallylic amine derivatives. The reaction proceeds with very high syn selectivity, which is the opposite of the stereochemistry observed for allylboration of imines. The reaction can be carried out with both aromatic and aliphatic acyl hydrazones. Based on our studies the excellent syn stereochemistry can be explained by chelation control of the acyl hydrazone and the B(OH)(2) moiety.

Direct allylation of aromatic and α,β-unsaturated carboxamides under ruthenium catalysis.

The ruthenium-catalyzed oxidative allylation of aromatic and α,β-unsaturated carboxamides with allylic carbonates is described. These transformations proceed readily with complete linear γ-selectivity of substituted allylic carbonates.

Direct Allylation of In Situ Generated Aldehyde Acyl Anions by Synergistic NHC and Palladium Catalysis

AbstractThe direct regioselective allylation of in situ generated aldehyde acyl anions has been achieved by synergistic NHC and Pd catalysis. It provides an efficient access to valuable β,γ‐unsaturated ketones under mild reaction conditions starting from easily accessible allylic carbonates and aldehydes without any preactivation. The synergistic catalysis method demonstrated herein adds a new dimension to the area of metal‐mediated C allylation.

Direct allylation of in situ generated aldehyde acyl anions by synergistic NHC and palladium catalysis.

The direct regioselective allylation of in situ generated aldehyde acyl anions has been achieved by synergistic NHC and Pd catalysis. It provides an efficient access to valuable β,γ-unsaturated ketones under mild reaction conditions starting from easily accessible allylic carbonates and aldehydes without any preactivation. The synergistic catalysis method demonstrated herein adds a new dimension to the area of metal-mediated C allylation.

Chemoselective and Direct Functionalization of Methyl Benzyl Ethers and Unsymmetrical Dibenzyl Ethers by Using Iron Trichloride

Methyl and benzyl ethers are widely utilized as protected alcohols due to their chemical stability, such as the low reactivity of the methoxy and benzyloxy groups as leaving groups under nucleophilic conditions. We have established the direct azidation of chemically stable methyl and benzyl ethers derived from secondary and tertiary benzyl alcohols. The present azidation chemoselectively proceeds at the secondary or tertiary benzylic positions of methyl benzyl ethers or unsymmetrical dibenzyl ethers and is also applicable to direct allylation, alkynylation, and cyanation reactions, as well as the azidation. The present methodologies provide not only a novel chemoselectivity but also the advantage of shortened synthetic steps, due to the direct process without the deprotection of the methyl and benzyl ethers.

Palladium catalyzed direct allylation of azlactones with simple allylic alcohols in the absence of any activators

The first example of the readily scalable direct allylic alkylation of azlactones with simple allylic alcohols has been developed, which is catalyzed by Pd(PPh3)4 alone in the absence of any activators under neutral conditions.

Direct allylation of alcohols using allyltrimethylsilane: a move towards an economical and ecological protocol for C–C bond formation

The allylation of benzylic, allylic and propargylic alcohols by means of allyltrimethylsilane represents one of the most powerful, elegant and practical methods for the formation of carbon–carbon bonds in organic synthesis. This method has received considerable attention owing to the ability of allylated compounds to undergo further synthetic manipulations. The aim of this review is to summarise the recent trends and developments reported in the literature and to assist in the creation of novel methodologies.

ChemInform Abstract: Protecting Group Free Diastereoselective C—C Coupling of 1,3‐Glycols and Allyl Acetate Through Site‐Selective Primary Alcohol Dehydrogenation.

AbstractThe direct allylation of various chiral diols is achieved with a Segphos‐derived iridium catalyst without the need for protecting groups, chiral auxiliaries and premetalated reagents.