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A method for the carboallylation of electron-deficient alkenes with tetraorganosilicon reagents and allylic carbonates based on Pd/Cu catalysis has been developed. This method affords a wide range of structurally diverse carbon skeletons from readily available starting materials, and tolerates various functional groups. [ABSTRACT FROM AUTHOR]

The reaction of aryl iodides, N‐tert‐butanesulfinamide, and allyl or homoallyl alcohol in the presence of a catalytic amount of Pd(OAc)2, NaHCO3 as a base, and TBAB leads to the formation of N‐tert‐butanesulfinyl imines in moderate yields. In this one‐pot process, a sequential Heck‐type arylation of the alkenol, isomerization of the double bond, and imine formation take place. [ABSTRACT FROM AUTHOR]

Abstract: Isoxazolinones are biologically and synthetically interesting densely functionalized heterocycles, which for a long time were not accessible in enantioenriched form by asymmetric catalysis. Next to the deficit of enantioselective methods, the functionalization of isoxazolinones is often plagued by regioselectivity issues due to the competition of various nucleophilic centers within the heterocycles. We report the first regio‐ and enantioselective C‐allylations of isoxazolinones. These occur with high regioselectivity in favor of the linear allylation products, although Ir phosphoramidite catalysts were used, which commonly results in branched isomers. Our studies suggest that this outcome is the result of a reaction cascade via an initial regio‐ and enantioselective N‐allylation to provide a branched allyl intermediate, followed by a spontaneous [3,3]‐rearrangement resulting in chirality transfer. [ABSTRACT FROM AUTHOR]

Abstract: A CoII/Box‐catalyzed [Box=bis(oxazoline)] enantioselective addition of potassium allyltrifluoroborate to cyclic ketimines was developed, providing the corresponding chiral α‐tertiary amines in high yields and with good enantioselectivity values. Alkoxycarbonyl‐ and alkyl‐substituted saccharin‐derived ketimines are suitable substrates for this allylation reaction. The product can be converted to complex molecules over several simple steps, including a precursor of MK‐0371, which is a kinesin spindle protein inhibitor. In addition, this catalytic system showed a strong positive nonlinear effect. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed oxa-[4+2] annulation of para-quinone methides with allyl carbonates bearing a nucleophilic alcohol side chain has been developed. This method provided an efficient strategy to the construction of 2-oxaspiro-cyclohexadienones via 1,6-conjugated addition-mediated allylation in moderate to good yields. Preliminary results on asymmetric derivatives promised potential in the synthesis of enantioenriched frameworks. [ABSTRACT FROM AUTHOR]

Enantioselective allylic substitution with enolates derived from aliphatic esters under mild conditions remains challenging. Herein we report iridium-catalyzed enantioselective allylation reactions of silyl ketene acetals, the silicon enolates of esters, to form products containing a quaternary carbon atom at the nucleophile moiety and a tertiary carbon atom at the electrophile moiety. Under relatively neutral conditions, the allylated aliphatic esters were obtained with excellent regioselectivity and enantioselectivity. These products were readily converted into primary alcohols, carboxylic acids, amides, isocyanates, and carbamates, as well as tetrahydrofuran and γ-butyrolactone derivatives, without erosion of enantiomeric purity. [ABSTRACT FROM AUTHOR]

The polarity reversal (umpolung) reaction is an invaluable tool for reversing the chemical reactivity of carbonyl and iminyl groups, which subsequent cross-coupling reactions to form C−C bonds offers a unique perspective in synthetic planning and implementation. Reported herein is the first visible-light-induced polarity-reversed allylation and intermolecular Michael addition reaction of aldehydes, ketones, and imines. This chemoselective reaction has broad substrate scope and the engagement of alkyl imines is reported for the first time. The mechanistic investigations indicate the formation of ketyl (or α-aminoalkyl) radicals from single-electron reduction, where the Hantzsch ester is crucial as the electron/proton donor and the activator. [ABSTRACT FROM AUTHOR]

The article focuses on the study regarding the synthesis of chlorosulfolipid mytilipin via longest linear sequence of only seven steps, which include highly diastereoselective haloallylation, complex vinyl epoxide kinetic resolution, and olefination. The study involves the oxidation with Dess-Martin period-inane and the conversion of sensitive and volatile aldehyde in crude form into vinyl epoxide. The study reveals the possibility for an eight-step enatioselective synthesis of mytilipin A.

We report a highly diastereo- and enantioselective allylation of azlactones catalyzed by the combination of a metallacyclic iridium complex and an optically inactive phosphate anion. The process demonstrates an approach for conducting diastereoselective reactions with prochiral nucleophiles in the presence of metallacyclic allyliridium complexes. The reaction provides access to an array of enantioenriched allylated azlactones containing adjacent tertiary and quaternary carbon centers. Preliminary mechanistic studies suggest that the phosphate and methyl carbonate anions together induce the unusually high diastereoselectivity. [ABSTRACT FROM AUTHOR]

An efficient coupling reaction of allyl acetate with (O-azaaryl)-carboxaldehyde by Pd-NHC dual catalysis has been developed. This reaction proceeds via direct coordination between the ortho nitrogen atom in the heterocycle and Pd(0). This dual catalysis is achieved under mild conditions to give 1,4-diones as products with up to 90% yield. [ABSTRACT FROM AUTHOR]

Promising results of an efficient and convenient strategy for the annulation of polycyclic aromatic compounds (PACs), employing orthoquinones as starting material and comprising allylation, pinacol rearrangement, ring-closing metathesis (RCM), and one-pot reduction followed by Wagner-Meerwein rearrangement, are presented. The strategy involves introducing triallylborane prepared in situ in the allylation step. Moreover, a novel expedient method for the preparation of 9,10-diallylphenanthrene was introduced. [ABSTRACT FROM AUTHOR]

An abstract of the article "Asymmetric Methallylation of Ketones Catalyzed by a Highly Active Organocatalyst 3,3'-F2-BINOL" by Y Zhang, et. al is presented.

Abstract: Various alkyl, aryl and hetaryl substituted allyl carbonates serve as substrates. [ABSTRACT FROM AUTHOR]

Abstract: 4‐ Mono‐ and disubstituted semicarbazides (III) and (VI) (25 examples) in all are obtained starting from bis(2,2,2‐trifluoroethyl)carbonate or 2,2,2‐trifluoroethylchloroformate and primary and secondary alkyl‐ and arylamines under conditions of parallel synthesis. [ABSTRACT FROM AUTHOR]