Product‐Derived Bimetallic Palladium Complex Catalyzes Direct Carbonylation of Sulfonylazides

Abstract

A novel product-derived bimetallic palladium complex catalyzes a sulfonylazide-transfer reaction with the σ-donor/π-acceptor ligand CO, and is advantageous given its broad substrate scope, high efficiency, and mild reaction conditions (atmospheric pressure of CO at room temperature). This methodology provides a new approach to sulfonylureas, which are present in both pharmaceuticals and agrochemicals. The synthesis of Glibenclamide on a gram scale further revealed the practical utility of this procedure. Mechanistically, the generation of a bridged bimetallic palladium species derived from the product sulfonylurea is disclosed as the crucial step for this catalytic cycle.

Synthesis of 11C‐labeled Sulfonyl Carbamates through a Multicomponent Reaction Employing Sulfonyl Azides, Alcohols, and [11C]CO

“…We were pleased to see a relatively large increase in conversion and NIRCY (entry 3), but increasing the temperature had a detrimental effect on both conversion and NIRCY (entries 4 and 5). Pd(OAc) 2 has been used in the synthesis of sulfonylureas from the corresponding sulfonyl chlorides and CO, but a conversion of 48 % and a non‐isolated radiochemical yield of 43 % prompted us to investigate Rh I as a catalyst. Earlier work in our group demonstrated the utility of Rh I in aminocarbonylation reactions of sulfonyl azides, and [Rh(COD)Cl] 2 and PPh 3 at 75 °C gave a conversion of 95 % and an NIRCY of 86 % (entry 7).…”

Recent Advances in the Synthesis of Sulfonylureas

“…This unexpected result was also observed under catalyst-and CO-free reaction conditions atmospheric pressure of CO at room temperature by using Pd (OAc) 2 as the pre-catalyst. [73] Noteworthy, the carbonylation reaction also worked in a one-pot fashion starting from aryl sulfonyl chlorides 78 and sodium azide (Scheme 28). As anticipated, the in situ formed isocyanates reacted with a range of amines 79, including secondary ones, to give sulfonylureas 80 in excellent yields.…”

“…Along with Odell, in the same year Zhang and co‐workers described the direct carbonylation of sulfonylazides under the atmospheric pressure of CO at room temperature by using Pd(OAc) 2 as the pre‐catalyst [73] . Noteworthy, the carbonylation reaction also worked in a one‐pot fashion starting from aryl sulfonyl chlorides 78 and sodium azide (Scheme 28).…”

Palladium‐Catalyzed Carbonylative Multicomponent Reactions

“…Through the successive nucleophilic substitution of sodium azide with sulfonyl chlorides and Pd(OAc) 2 ‐catalyzed aminocarbonylation of sulfonylazides, Zhang and co‐workers developed a facile four‐component pathway to afford sulfonylurea derivatives with excellent yields under mild conditions (Scheme a) . This protocol was applied to the gram scale synthesis of the antidiabetic drug Glibenclamide (Scheme b).…”