Gold(I)-catalyzed amination of allylic alcohols with cyclic ureas and related nucleophiles

Gold(I)-catalyzed enantioselective intramolecular dehydrative amination of allylic alcohols with carbamates

A 1:2 mixture of [(S )-2 ](AuCl)2 [(S )-2 = (S )-DTBM-MeOBIPHEP] and AgClO4 catalyzes the intramolecular enantioselective dehydrative amination of allylic alcohols with carbamates to form five- and six-membered aliphatic nitrogen heterocycles in high yield with up to 95% ee .

Regio- and enantioselective hydroamination of dienes by gold(I)/menthol cooperative catalysis

Alcohol is key: regio- and enantioselective hydroamination of 1,3-dienes has been achieved with the dinuclear catalyst (R)-DTBM-SEGPHOS. The rate and selectivity of the reaction are enhanced by alcohol additives like menthol, which coordinates the cationic gold(I) to generate a Brønsted acid that can participate in catalysis. Mbs=p-methoxybenzenesulfonyl.

Substrate-directable Heck reactions with arenediazonium salts. The regio- and stereoselective arylation of allylamine derivatives and applications in the synthesis of naftifine and abamines

The palladium-catalyzed, substrate-directable Heck-Matsuda reaction of allylamine derivatives with arenediazonium salts is reported. The reaction proceeds under mild conditions, with excellent regio- and stereochemical control as a function of coordinating groups present in the allylamine substrate. The distance between the olefin moiety and the carbonylic system seems to play a key role regarding the regiocontrol. The method presents itself as robust, as simple to carry out, and with wide synthetic scope concerning the allylic substrates and the type of arenediazonium employed. The synthetic potential of the method is illustrated by the short total syntheses of the bioactive compounds naftifine, abamine, and abamine SG.

Gold(I)-catalyzed synthesis of γ-vinylbutyrolactones by intramolecular oxaallylic alkylation with alcohols

Gold(I)-N-heterocyclic carbene (NHC) complexes proved to be a reliable catalytic system for the direct synthesis of functionalized γ-vinylbutyrolactones by intramolecular oxaallylic alkylation with primary alcohols. Good isolated chemical yields were obtained for a range of malonyl and acetate derivatives. The good performance in reagent-grade solvents and the functional group/moisture tolerance make this catalytic process a promising route for the synthesis of architecturally complex polycyclic structures.

Recent advances in the gold-catalyzed additions to C-C multiple bonds

C-O, C-N and C-C bonds are the most widespread types of bonds in nature, and are the cornerstone of most organic compounds, ranging from pharmaceuticals and agrochemicals to advanced materials and polymers. Cationic gold acts as a soft and carbophilic Lewis acid and is considered one of the most powerful activators of C-C multiple bonds. Consequently, gold-catalysis plays an important role in the development of new strategies to form these bonds in more convenient ways. In this review, we highlight recent advances in the gold-catalyzed chemistry of addition of X-H (X = O, N, C) bonds to C-C multiple bonds, tandem reactions, and asymmetric additions. This review covers gold-catalyzed organic reactions published from 2008 to the present.

A comparative study of the Au-catalyzed cyclization of hydroxy-substituted allylic alcohols and ethers

The Au(I)-catalyzed cyclization of hydroxyallylic ethers to form tetrahydropyrans is reported. Employing (acetonitrile)[(o-biphenyl)di-tert-butylphosphine]gold(I) hexafluoroantimonate, the cyclization reactions were complete within minutes to hours, depending on the substrate. The reaction progress was monitored by GC, and comparisons between substrates demonstrate that reactions of allylic alcohols are faster than the corresponding ethers. Additionally, it is reported that Reaxa QuadraPure^TM MPA is an efficient scavenging reagent that halts the reaction progress.

Gold(I)-catalyzed intramolecular amination of allylic alcohols with alkylamines

A 1:1 mixture of (1)AuCl [1 = P(t-Bu)(2)o-biphenyl] and AgSbF(6) catalyzes the intramolecular amination of allylic alcohols with alkylamines to form substituted pyrrolidine and piperidine derivatives. Gold(I)-catalyzed cyclization of (R,Z)-8-(N-benzylamino)-3-octen-2-ol (96% ee, 95% de) led to isolation of (R,E)-1-benzyl-2-(1-propenyl)piperidine in 99% yield with 96% ee, consistent with the net syn addition of the amine relative to the departing hydroxyl group.