One‐Pot Catalyst‐Free Direct Sulfenylation of 1‐Aryl Pyrazolones with Aryl Thiols at Room Temperature

• Published in: ChemistrySelect (Weinheim) 2017-10, Vol.2 (30), p.9670-9673
• Main Authors: Kamani, Ronak D., Purohit, Vishal B., Thummar, Rahul P., Sapariya, Nirav H., Vaghasiya, Beena K., Patel, Kirit H., Pashavan, Chandankumar T., Shah, Manish K., Raval, Dipak K.
• Format: Article
• Language: English
• Subjects: N-chlorosuccinimide (NCS); Oak Ridge Thermal-Ellipsoid Plot Program (ORTEP); Pyrazole; single crystal X-ray diffraction (XRD)
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.201701924

A novel strategy for N‐chlorosuccinimide mediated direct sulfenylation of 1‐aryl pyrazolones using aryl thiols has been developed at room temperature. The protocol was found to be simple, efficient and transition metal‐free to afford the target products in good to excellent yields without further purification. The prepared compounds were characterised by 1H NMR, 13C NMR and IR spectroscopy. The skeleton of one of the synthesized compounds has been well confirmed by X‐ray single crystal diffraction (XRD) analysis as well as ORTEP diagram. N‐chlorosuccinimide (NCS) promoted novel protocol for the direct sulfenylation of 1‐aryl pyrazolones using variety of thiols has been successfully achieved at room temperature. This strategy is simple, efficient and transition metal‐free to afford the sulfenylated pyrazoles in excellent yields without the use of column chromatography which makes the protocol very interesting compared to the conventional sulfenylation reactions of 1‐aryl pyrazolones.