Concise Approach to Benzisothiazol-3(2H)-one via Copper-Catalyzed Tandem Reaction of o-Bromobenzamide and Potassium Thiocyanate in Water

Abstract

A concise approach to various benzisothiazol-3(2H)-one derivatives has been developed by copper-catalyzed the reaction of o-bromobenzamide derivatives with potassium thiocyanate (KSCN) in water. The reaction proceeds via a tandem reaction with S-C bond and S-N bond formation.

Transfer of Sulfur: From Simple to Diverse

“…The Cu‐catalyzed reaction of o ‐halobenzamide derivatives with potassium thiocyanate in water was demonstrated to synthesize benzisothiazol‐3(2 H )‐one derivatives through a tandem reaction with SC and SN bond formations (Scheme ) 41…”

“… Cu‐catalyzed synthesis of benzisothiazol‐3(2 H )‐one derivatives by Chen, Xi, and co‐workers 41. DABCO=1,4‐diazabicyclo[2.2.2]octane.…”

Copper(II)‐Catalyzed Three‐Component Cascade Annulation of Diaryliodoniums, Nitriles, and Alkynes: A Regioselective Synthesis of Multiply Substituted Quinolines

“…[7][8][9] Our goal is to efficiently synthesize nitrogen-containing heteroarenes from diaryl iodonium salts. [10] When a mixture of diphenyliodonium 1 a (0.5 mmol), phenyl acetylene 2 a (1.0 mmol), and benzonitrile 3 a (1.0 mmol) with Cu(OTf) 2 (0.05 mmol) as catalyst was heated at 120 8C in 1,2-dichloethane (DCE) for 12 h, 2,4-diphenylquinoline 4 a was obtained in 88 % yield (determined by GC with n-dodecane as internal standard; 73 % yield upon isolation). The temperature, solvent, and stoichiometry of the reagents were screened to optimize the reaction conditions (Table 1; see Supporting Information for more details).…”

An efficient approach to construct benzisothiazol-3(2H)-ones via copper-catalyzed consecutive reaction of 2-halobenzamides and carbon disulfide

“…Therefore, this approach showed high functional group tolerance and proved to be a quite general methodology for the preparation of multifarious benzisothiazol-3(2H)-one derivatives. 22 to give the target product 2. The generating red carbon monosulfide (CS) was observed during the purification process, which could be trapped by some nucleophilic amines due to its weak electrophilicity 28 (see Supporting information).…”

“…Therefore, various chlorinefree synthetic methods have been developed, including reactions of 2-sulfenamoylbenzoates 12 , 3H-1,2-benzodithiol-3one 1-oxide 13 or 1,3-benzoxathiin-4-one 1-oxides 14 with various primary amines, reaction of 2-mercaptobenzoic acid with diphenyl phosphoryl azide (DPPA) 15 or hydroxylamine hydrochloride 16 in one pot, reactions of 2mercaptobenzamides with oxidation reagents 17 or hydroxylamine-O-sulfonic acid 12c , reactions of 2,2'dithiodibenzoates with acetamide or urea via one-pot amidation-cyclization process 18 , reactions of 2,2'dithiodibenzamides with O-methylhydroxylamine hydrochloride (OMAH) 19 , and intramolecular cyclization of 2-(tbutyl sulfoxide)benzamides or 2-(benzyl sulfoxide)benzamides 20 . Recently, several copper-catalyzed tandem reactions have been applied to synthesis benzisothiazol-3(2H)-ones, starting from 2-halobenzamides and sulfur 21 (or potassium thiocyanate 22 Carbon disulfide (CS 2 ) is a well-known building block for the efficient construction of sulfur-containing heterocycles in synthetic chemistry from the viewpoints of operational simplicity, economic raw material, and assembly efficiency. 24 However, it is of interest to note that CS 2 used as a sulfur source in the reaction involving C-S and S−N bond formation is rare in the construction of heterocyclic compounds.…”