Palladium‐Catalyzed Desulfitative Arylation of 5‐Alkoxy‐3,4‐dibromo‐2(5H)‐furanone with Sodium Arylsulfinates

Abstract

A palladium‐catalyzed desulfitative arylation reaction of 5‐alkoxy‐3,4‐dibromo‐2(5H)‐furanones to provide 5‐alkoxy‐4‐aryl‐3‐bromo‐2(5H)‐furanones is reported. This reaction has a high reaction site selectivity, which can realize arylation at the C4‐position. Various sodium arylsulfinates are well tolerated under the mild reaction conditions. The current study makes the arylation of general alkenyl halides possible by the use of cheap and easily available sodium arylsulfinates as aryl sources.

Copper(I)‐Catalyzed Alkyl‐ and Arylsulfenylation of 3,4‐Dihalo‐2(5H)‐furanones (X=Br, Cl) with Sulfoxides under Mild Conditions

“…For organic chemists, killing two birds with one stone in organic synthesis is usually welcome, and many reactions simultaneously using solvent as a substrate have been developed recently ,. Being interested in 2(5 H )‐furanone chemistry,, we surprisingly discovered that sodium arylsulfinates can react with solvent DMSO and 3,4‐dibromo‐5‐methoxy‐2(5 H )‐furanone ( 1a ) to give arylsulfonyldibromomethane (Scheme b) when investigating the effect of solvents on the Pd‐catalyzed desulfitative arylation of 1a with sodium arylsulfinates (Scheme a) . And excitingly, the substitution of inexpensive Cu catalysts for Pd salts in optimizing the catalyst fortunately gave an unexpected methylthiolation (Scheme c).…”

Synthesis and Biological Properties of 2(5H)-Furanones Featuring Bromine Atoms on the Heterocyclic Ring and/or Brominated Substituents

“…More recently, Wang and coworkers developed an efficient protocol for the synthesis of 5-alkoxy-4-aryl-3bromo-2(5H)-furanones 47 [55]. It involved the PdCl 2 /PPh 3 -catalyzed desulfitative regioselective arylation of 5-alkoxy-3,4-dibromo-2(5H)-furanones 45 with sodium arylsulfinates 46 as aryl source (Scheme 16).…”

“…It involved the PdCl 2 /PPh 3 -catalyzed desulfitative regioselective arylation of 5-alkoxy-3,4-dibromo-2(5H)-furanones 45 with sodium arylsulfinates 46 as aryl source (Scheme 16). The reaction was carried out in toluene under reflux using NaHCO 3 as the base providing compounds 47 in yields ranging from 62 to 82% [55].…”

“…The synthesis began with the reaction of 52 with LDA in THF at -78 °C and addition of 1-bromo-4-phenylbutan-2-one (53) to the resulting lithium derivative, followed by basification with aqueous NaOH, which gave 1-bromo-3hydroxyprop-1-enyl p-tolyl sulfoxide (54) in 91% yield. The subsequent reaction of 54 with phenyl chloroformate (55) in CHCl 3 in the presence of pyridine gave sulfoxide 56 in 83% yield. Finally, the nucleophilic cyclization of the magnesium alkylidene carbenoid generated from 56 and i-PrMgCl•LiCl (57) provided compound 58 in 46% yield (Scheme 18) [60].…”

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

“…In recent years, the readily accessible sodium arylsulfinates have attracted considerable attention in organic synthesis as precursors in various cross-coupling reactions due to the easy availability and the compatibility with numerous functional groups. Interestingly, sodium arylsulfinates were also reported as the coupling partners for the Pd-catalyzed desulfitative coupling reactions, such as desulfinative Heck-type, [36][37][38] addition reactions to double or triple bonds, [39][40][41][42][43] as well as cross-coupling [44][45][46][47][48][49] and C-H arylation [50][51][52][53][54][55][56][57][58][59] reactions have been well developed. [60] Moreover, the related reaction conditions were found much milder than those reported for the corresponding aryl carboxylic acids.…”