Pd‐catalyzed Desulfitative reaction of Aryltrifluoroborates with sodium Arenesulfinates in water

Abstract

An efficient procedure for the synthesis of biaryls was catalyzed by Pd(CH 3 CN) 4 (BF 4 ) 2 is reported. This Pd-catalyzed cross-coupling reaction of aryltrifluoroborates with sodium arenesulfinates was developed under mild and environmentally benign conditions, in water without any ligand or additive. The reaction gave a range of structurally diverse unsymmetrical bi-aryl molecules with excellent yields, in which the byproduct was sulfur dioxide. It is worth noting that this protocol is also applicable to many heterocyclic aromatics such as thiophene, furan, pyridine, quinoline, isoquinoline and indole.

Indolylboronic Acids: Preparation and Applications

“…Selected examples show how chloro- [29], bromo- [30], bromoindolyl phosphate [31], and triflates [32] are all capable of coupling with boronic acids under mild reaction conditions. Yet, a wide variety of allylic alcohols [33], heterocyclic halides [34], bromoenol phosphates [35], sulfones [36], and sulfonates [37] have been used as electrophilic templates in reactions with indolylboronic acids under Suzuki-Miyaura reaction conditions involving, for example EvanPhos [38] and tri- tert -butylphosphine ligand [39], nickel [40], and rhodium [41] catalysts, as well as asymmetric transformations [42,43]. The abovementioned examples illustrate the practical application of the Suzuki-Miyaura reaction by means of both electrophilic and nucleophilic indolyl templates for the synthesis of substituted indoles.…”

Copper-Catalyzed Synthesis of Masked (Hetero)Aryl Sulfinates

“…Aryl sulfinates , are key precursors for the synthesis of medicinally relevant sulfonyl derivatives, including sulfones, sulfonamides, and sulfonyl halides . Sulfinates are also versatile synthetic reagents, with the potential to react as either “electrophilic” − or “nucleophilic” − components in cross-coupling reactions. Classical syntheses of sulfinates often require harsh reaction conditions and toxic reagents; methods include the reduction of sulfonyl chlorides using zinc, oxidation of thiols with hydrogen peroxide, or the insertion of toxic SO 2 gas into organometallics .…”