B-Alkyl sp³–sp² Suzuki–Miyaura Couplings under Mild Aqueous Micellar Conditions

Abstract

Use of B-sp-alkyl reagents for Suzuki-Miyaura couplings under aqueous micellar catalysis conditions is reported. Studies as to substrate scope, use in a four-step one-pot sequence, and reaction medium recycling exemplify the synthetic utility of this technology. OBBD ( B-alkyl-9-oxa-10-borabicyclo[3.3.2]decane) derivatives are easily made and utilized for couplings under mild conditions. Comparisons were also made between OBBD and 9-BBN ( B-alkyl-9-borabicyclo[3.3.1]nonane) derivatives as reaction partners.

Regioselective Benzylic C–H Alumination and Further Functionalization of 2-Alkylpyridines by Yttrium Catalyst

“…Next, Pd-catalyzed cross-coupling reaction of the resulting (pyridin-2-yl)­methyl aluminum species with aryl iodide was examined. In contrast to the cross-coupling reactions of organomagnesium, organozinc, organoboron, and organostannan with aryl halides that are widely studied and recognized as excellent methods for C–C bond formation in organic synthesis, the number of the reports on the similar cross-coupling reaction of organoaluminum reagents has been still limited. − In most of such reports, transferable organic ligands from the aluminum center are limited to unsaturated groups, such as aryl, alkenyl, and alkynyl groups, except some examples that use methylaluminum reagents bearing a specific heteroatom ligand, i.e., the cross-coupling reactions, which can transfer an alkyl group, especially bearing a relatively complex structure, have been rarely reported . Therefore, investigating the cross-coupling reaction of the (pyridin-2-yl)­methyl aluminum species resulting from the current C–H alumination of 2-alkylpyridines would be an interesting challenge.…”

Palladium/NHC (NHC = N-Heterocyclic Carbene)-Catalyzed B-Alkyl Suzuki Cross-Coupling of Amides by Selective N–C Bond Cleavage

“…Despite recent progress in C­(acyl)–aryl cross-couplings of amides, ,,− alkylation of amide bonds by transition-metal catalysis remains a significant challenge due to competing β-hydride elimination/protodemetalation decomposing the organometallic and slower transmetalation . In previous work, Ni-catalyzed alkylation of N-Ts activated amides using alkylzinc reagents and Ni-catalyzed alkylation of N-Ph/Me activated amides using alkylborane reagents has been reported . Furthermore, a Ni-catalyzed reductive C­(acyl)–alkyl cross-coupling of N-acyl-succinimide amides has been reported .…”

Recent Progress of Metal Nanoparticle Catalysts for C–C Bond Forming Reactions

“…One of the most effective catalytic systems is micellar catalytic systems, which have been developed and expanded by Lipshutz and Handa groups. In their reaction systems, several reactions proceed at room temperature by designing an appropriate surfactant which form a micellar reaction field in water (Scheme 30) [315][316][317][318][319][320][321][322][323][324][325][326][327][328]. Scheme 30.…”