C-H bond chlorination and bromination using water soluble nickel(II) guanidine complexes
Jaipriya Khatri1, Vasanthapandiyan Mari1, Aniruddha Sarkar2
1Department of Chemistry, School of Natural Sciences, Shiv Nadar Institution of Eminence Deemed to be University, Delhi NCR, Gautam Buddha Nagar, Dadri, UP-201314, India. basabbijayi@gmail.com.
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Water-soluble nickel(II)-guanidine-based complexes successfully catalyzed the C-H chlorination of a series of hydrocarbons in the presence of NaOCl and acetic acid in water-chloroform (7 : 3, biphasic condition) at room temperature. Majorly chlorinated products (TON ∼680 for cyclohexane) were obtained. Furthermore, C-H bond bromination of cyclohexane, n-hexane, and toluene was also carried out using in situ generation of NaOBr. These putative formations of Ni(III) species were characterized by electron paramagnetic resonance (EPR) spectroscopy, and the plausible mechanism for chlorination was confirmed by DFT calculations.
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