Intra- and Intermolecular C−S Bond Formation Using a Single Catalytic System: First Direct Access to Arylthiobenzothiazoles

Abstract

We have for the first time developed two ligand-assisted Cu(I)-catalyzed sequential intra- and intermolecular S-arylations leading to the direct synthesis of arylthiobenzothiazoles in one pot without an inert atmosphere. Low catalyst loading, inexpensive metal catalyst and ligand, lower reaction temperature, and shorter reaction times make this method superior to all reported methods for the synthesis of arylthiobenzothiazole.

Transition‐Metal‐Catalyzed CS Bond Coupling Reaction

“…The key step of this strategy is a sequential intra-and intermolecular S-arylation (Scheme 18). [33] The authors have also studied the effect of various ligands and found that 22 was the best one for these transformations. The dithiocarbamates (21) were prepared through the reaction of 2-bromoaniline derivatives with CS 2 and triethylamine.…”

“…More importantly, the authors have found that aromatic halides containing an electronwithdrawing group on the phenyl ring undergo C À S coupling with thiols in the absence of catalyst to afford the corresponding thioethers in good yields (path B, Scheme 41). [65] Subsequently, a similar CÀS bond forming reaction of aromatic halides with aromatic thiols using a slightly different NHC (33) and NiA C H T U N G T R E N N U N G (OAC) 2 as a catalyst has also been achieved to yield the resulting diaryl thioethers in good yields (path C, Scheme 41). [66] Nickel-catalyzed inter-and intramolecular CÀS bond formation by cross-coupling between aryl halides and aryl-and alkyl thiols has been developed (Scheme 42).…”

Organometallic Approaches to Carbon–Sulfur Bond Formation

“…Likely, the function of each ligand is in solubilizing the copper precatalyst and preventing aggregation of any active copper species in solution [59]. Arylation can be promoted by the use of microwave or additives, including nanoparticles [60][61][62][63][64][65].…”

Development of Divergent Synthetic Methods of Pyrimidobenzothiazine and Related Tricyclic Heterocycles

“…With these findings [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53], the author investigated the transition-metal (Pd, Cu, Fe, etc.) catalyzed coupling of haloarenes 6aa and heterocumulenes.…”