Copper(I)‐Induced Sulfenylation of H‐Phosphonates, H‐Phosphonites and Phosphine Oxides with Aryl/alkylsulfonylhydrazides as a Thiol Surrogate

Abstract

Aerobic dehydrogenative sulfenylation of H-phosphonites, and phosphine oxides with aryl/alkylsulfonyl hydrazides catalyzed by a sub-stoichiometric amount of copper iodide has been accomplished. This protocol is compatible with functional groups, and results in various thiophosphate derivatives in good to high yields.

Across the Board: Brent H. Shanks

“…Recently we reported the use of monosubstituted sulfonyl hydrazides (RSO 2 NHNH 2 ) as sulfenyl sources in the synthesis of indole thioethers 11. Later on, they were disclosed by Singh,12 Jiang,13 Xiang, Yuan,14 Kumaraswamy,15 Zhao, Lu,16 Yan, Huang,17 and us18 to undergo sulfenylation with carbon‐carbon multiple bonds, carbon‐hydrogen bonds, carbon‐halogen bonds, and phosphorus‐hydrogen bonds under various conditions. When compared with commonly used sulfenylating agents such as thiols, disulfides, sulfenyl halides, sulfenamides, and sulfenate esters, sulfonyl hydrazides are readily accessible solids, free of unpleasant odor, and compatible with moisture.…”

Recent Advances in Sulfur‐Centered S–X (X = N, P, O) Bond Formation Catalyzed by Transition Metals

“…Raju and co-workers [48] successfully developed a mild, basefree method for the S-P bond formation using odorless, airstable sulfonylhydrazides as sulfur source and H-phosphonates as phosphine source [Eq. (32)].…”

An Alternative Metal-Free Aerobic Oxidative Cross-Dehydrogenative Coupling of Sulfonyl Hydrazides with Secondary Phosphine Oxides

“…Based on the aforementioned results and previous reports, a plausible mechanism is proposed by analogy with cross-dehydrogenative coupling reactions. 11,14 Initially, iodine ions from TBAI react with oxygen to generate an iodine(I) peroxo species, which then dissociates in the presence of the sulfonyl hydrazide resulting in organic peroxide Int-A and hypoiodous acid (HOI). Next, sequential removal of hydrogen and oxygen atoms from putative Int-A could lead to thiodiazonium salt Int-B.…”

“…10 In 2014, Kumaraswamy and Raju developed an aerobic dehydrogenative sulfenylation of secondary phosphine oxides with sulfonyl hydrazides catalyzed by CuI for the preparation of phosphinothioates (Scheme 1, B). 11 However, despite these advances, the involved starting materials, R 2 P(O)X (X = Cl, Br) and RSX (X = H, Cl, Br, CN, SAr), were often very odorous, toxic or moisture-sensitive reagents. [4][5][6][7][8][9] Furthermore, the aforementioned methods frequently required transition-metal catalysis and stoichiometric amounts of strong bases and oxidants.…”