Enantiospecific and Iterative Suzuki–Miyaura Cross-Couplings

Abstract

The Suzuki-Miyaura cross-coupling reaction has emerged as one of the most powerful methods for the construction of carbon-carbon bonds. Though most widely utilized for the synthesis of sp-sp linkages, the use of this reaction to form stereochemistry-bearing sp-sp bonds has received widespread attention over the past decade. This Perspective highlights approaches to the synthesis of enantioenriched molecules via the Suzuki-Miyaura reaction. Particular focus is placed on the use of enantiomerically enriched organoboron compounds as coupling partners in stereospecific processes, as well as the development of enantioconvergent and group-selective reactions. In addition, progress in the development of chemoselective, iterative cross-coupling methods will be discussed.

Sterically Unprotected Nucleophilic Boron Cluster Reagents

“…This observation stands in stark contrast to existing metal-catalyzed systems, in which racemic borylated products are observed due to the intermediacy of alkyl radicals, therefore impeding general approaches to stereospecific borylation through chiral induction 22,23 . Importantly, this borylation strategy provides a new chiral auxiliary-free pathway to generate enantio-enriched alkyl boronates from chiral alcohol derivatives 24,25 . Undesired side reactions, including apparent one-electron reduction chemistry, have been observed with other classes of nucleophilic boron reagents in the presence of alkyl-based electrophiles 26 ; in addition, some of these species also exhibit reducing behavior toward main group electrophiles 27 .…”

The Problem with Problems: Fundamental to Applied Research Using Palladium

“…19 Other excellent work in the area of selective Suzuki-Miyaura cross-coupling exploiting reactivity of alkyl diboron systems has been reported by Shibata, 20 Morken, 21 Hall, 22 Crudden, 23 and others -an excellent review of this area was published by Crudden. 24,25 Scheme 6 (a) Use of the MIDA protecting group in Suzuki-Miyaura cross-coupling. (b) Use of the DAN protecting group in Suzuki-Miyaura cross-coupling.…”

Synthesis of Stereodefined Borylated Dendralenes through Copper‐Catalyzed Allylboration of Alkynes

“…[24] Importantly,t he presence of ac hiral boronic ester opens new possibilities for the transformation of the decalin system through stereospecific couplings. [25] Another interesting feature of the borylated dendralene framework is that new dendralenes can be readily accessed from asame precursor by exploiting the reactivity of the CÀB bond. This was exemplified by the synthesis of compounds 9 and 11 using Pd-catalyzed stereoretentive Suzuki crosscoupling with 2-bromotoluene 8 and b-bromostyrene 10 (Scheme 5a).…”