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The Suzuki–Miyaura cross-coupling is one of the most often utilized reactions in the synthesis of pharmaceutical compounds and conjugated materials. In its most common form, the reaction joins two sp2-functionalized carbon atoms to make a biaryl or diene/polyene unit. These substructures are widely found in natural products and small molecules and thus the Suzuki–Miyaura cross-coupling has been proposed as the key reaction for the automated assembly of such molecules, using protecting group chemistry to affect iterative coupling. We present herein, a significant advance in this approach, in which multiply functionalized cross-coupling partners can be employed in iterative coupling without the use of protecting groups. To accomplish this, the orthogonal reactivity of different boron substituents towards the boron-to-palladium transmetalation reaction is exploited. The approach is illustrated in the preparation of chiral enantioenriched compounds, which are known to be privileged structures in active pharmaceutical compounds., The Suzuki-Miyaura cross coupling is widely used in industrial and academic settings for the formation of carbon-carbon bonds. Here, the authors report a procedure whereby a molecule with multiple reactive carbon-boron bonds can undergo sequential, selective Suzuki-Miyaura reactions without the need for protecting groups.

A catalytic asymmetric synthesis of a key intermediate for ottelione has been achieved using oxidative desymmetrization as the critical step. This oxidative desymmetrization was efficiently promoted by an iridium diamine complex to give the desired hydroxy ketone in >99% ee and 60% yield.

A new and efficient method has been developed for the regio- and chemoselective synthesis of β -hydroxysulfides with the ring-opening reaction of 1,2-epoxides by diaryl disulfides and zinc powder in the presence of a catalytic amount of BiCl 3 in molten tetrabutyl phosphonium bromide as an ionic liquid.

Asymmetric tandem coupling of meso-diols with aldehydes was achieved by using a chiral iridium catalyst. This tandem reaction consists of oxidative desymmetrization of the meso-diol, aldol condensation with an aldehyde, and reduction of the enone intermediate. A one-pot method using an excess of a hydrogen donor gave α-benzyl-β-hydroxyindan-1-ones in up to 94% ee and 88% yield. An asymmetric hydrogen autotransfer method in the absence of an additional hydrogen donor gave the desired benzyl ketone in 92% ee.

A facile and efficient synthesis of β-amino alcohols by ring opening of epoxides with anilines in good to excellent yields in the presence of catalytic amounts of Bi(TFA) 3 or Bi(OTf) 3 via the use of molten tetrabutylammonium bromide (TBAB) as an ionic liquid is described. In addition, the observed chemoselectivity can be considered as a noteworthy advantage of this method.

The Suzuki-Miyaura cross-coupling of enantioenriched secondary allylic boronic esters occurs with high γ-regioselectivity and high retention of chirality, proceeding via γ-selective transmetalation and subsequent reductive elimination.

Asymmetric tandem coupling of meso-diols (I) with aldehydes is achieved using a chiral Ir-catalyst.

The catalytic oxidative desymmetrization of meso-diols was realized using a chiral iridium catalyst. In particular, the reaction is effective for the cyclic diols to give the corresponding hydroxy ketones in high chemical yields with high ee's. With this reaction as a key step, a short-step synthesis of common intermediate of ottelione and scyphostatin was achieved.

Asymmetric cross-coupling reactions in which stereo- chemistry-bearing CC bonds are created are still in their infancy. Considering the wealth of compounds that can be prepared by cross-coupling methodologies, and the impor- tance of synthetic methods leading to enantiomerically en- riched products, this is a surprising reality. Advances in this area have occurred in the past few years, in the realm of enantioselective or enantiospecific cross-couplings of chiral electrophiles. (1) In the area of cross-coupling of stereodefined nucleo- philes, Crudden originally reported the enantiospecific cross-coupling of chiral enantiomerically enriched benzylic boronic esters (Eq. (1)). (2, 3)

Pd-catalyzed cross-coupling reactions of secondary allylic boronic esters (I) with aryl iodides (II) are performed under the conditions previously described for the coupling of benzylic substrates.

A new and efficient method has been developed for the regio- and chemoselective synthesis of β -hydroxysulfides with the ring-opening reaction of 1,2-epoxides by diaryl disulfides and zinc powder in the presence of a catalytic amount of BiCl 3 in molten tetrabutyl phosphonium bromide as an ionic liquid.

Diaryl disulfides undergo regioselective ring-opening of 1,2-epoxides in the presence of zinc powder and 3-4 mol-% of bismuth(III) trifluoroacetate or 1 mol-% of bismuth(III) triflate in molten tetrabutylphosphonium bromide (TBPB) to afford the corresponding β-hydroxy thioethers in good to excellent yields.

A new convenient method has been developed for the synthesis of beta-hydroxy thioethers with aryl disulfides and zinc powder in the presence of catalytic amounts of Bi(OTf)3 and Bi(TFA)3 in acetonitrile. The present method is very simple and the conditions tolerate a variety of acid-sensitive protecting groups. On the other hand, alkyl or benzyl disulfides afforded no corresponding thioethers under similar conditions. Then the observed regio- and chemoselectivity can be considered as a noteworthy advantage of this method. Um método novo e conveniente foi desenvolvido para a síntese de beta-tioéteres com disulfetos arílicos e zinco em pó, na presença catalítica de Bi(OTf)3 e Bi(TFA)3 em acetonitrila. O presente método é bastante simples e tolera uma variedade de grupos ácidos protetores. Entretanto, disulfetos arílicos e benzílicos não fornecem os correspondentes tioéteres nas mesmas condições. Assim, a regio- e quimiosseletividade observada pode ser apontada como uma vantagem destacada deste método.

Bismuth(III) trifluoromethanesulfonate and trifluoroacetate are highly efficient and practical catalysts for oxirane ring opening in reactions of epoxides with substituted anilines. The reactions are characterized by high chemoselectivity and good to excellent yields of the products.

A new, efficient, clean, and regioselective 'one-pot' procedure for thiolyzation of epoxides with aryl disulfides catalyzed by cerium(III) chloride heptahydrate immobilized on tetrabutyl phosphonium bromide as an ionic liquid is reported.

A facile and environmentally friendly methodology for ring opening of epoxides with anilines has been developed in the presence of catalytic amounts of bismuth (III) triflate or bismuth (III) trifl...

A new, efficient, clean, and regioselective 'one-pot' procedure for thiolyzation of epoxides with aryl disulfides catalyzed by cerium(III) chloride heptahydrate immobilized on tetrabutyl phosphonium bromide as an ionic liquid is reported.

A facile and environmentally friendly methodology for ring opening of epoxides with anilines has been developed in the presence of catalytic amounts of bismuth (III) triflate or bismuth (III) trifl...

Diaryl disulfides undergo regioselective ring-opening of 1,2-epoxides in the presence of zinc powder and 3-4 mol-% of bismuth(III) trifluoroacetate or 1 mol-% of bismuth(III) triflate in molten tetrabutylphosphonium bromide (TBPB) to afford the corresponding β -hydroxy thioethers in good to excellent yields.