ORIGINAL ARTICLE The article was published by ACG Publications http://www.acgpubs.org/journal/organic-communications © April-June 2023 EISSN:1307-6175 DOI: http://doi.org/10.25135/acg.oc.153.2304.2760 Available online:June 27, 2023 Org. Commun. 16:2 (2023) 108-116 Efficient and regioselective acetylation of benzene derivatives with Ac2O in the presence of mercurytetrathiocyanatocobaltate (II) Aayesha Nasreen * Department of Chemistry, College of Sciences, Jazan University, Jazan, 45142, P.O Box No. 114, Kingdom of Saudi Arabia (Received April 29, 2023; Revised June 20, 2023; Accepted June 24, 2023) Abstract: Based on Friedel Crafts acylation, an efficient and facile method for the chemo-selective as well as region-selective acylation of substituted benzene derivatives has been developed by using Hg[Co(SCN)4] as catalyst. The reaction is highly chemo-selective as well as region-selective as only acetophenones were obtained, whereas the benzophenones are not formed. The present method is very efficient with simple work up gives the products in good to excellent yield. The reaction is carried out using CHCl3 as solvent at room temperature. It is anticipated that the present newly developed method will open a gateway for the chemist to prepare the chemo as well as region-selective acetophenones. Keywords: Regioselective; Hg[Co(SCN)4], aromatic ketones. ©2023 ACG Publication. All rights reserved. 1. Introduction The Friedel-Crafts (FC) acylation reaction of aromatics with acid halides or acetic anhydride is a fundamental and important reaction in organic synthesis. 1-3 The region-selective FC acylation to produce aromatic ketones in chemical industry is a important conversion as they are useful intermediates in the preparation of various synthetic intermediates, 4 chemical feed stocks, 5 pharmaceuticals 6 and fine chemicals. 7 Although, the aromatic ketones have numerous applications in organic synthesis but their conventional methods to produce them has limitations such as complicated synthetic procedures and environmentally hazardous conditions, 8-9 the use of homogeneous catalysts, for example, protic acids, 10 soluble metal halides 11 and substituted anhydrides 12 in stoichiometric amounts and other homogeneous catalysts, i.e., Ln(OTf)3-LiClO4, 13 LiClO4-acyl anhydride complex, 14 (PhCN)2PtCl2/AgSbF6 15 and Re-Br(CO)5. 16 The industrial application of these homogeneous catalysts is also associated with various shortcomings because of the non-economical reaction process and environmental issues. 17 Therefore, design and development of a highly efficient and economical catalyst system with less environmental disputes is in immense need to overcome these challenges. Certain efforts have been put on for the development of FCR in the recent years for example the synthesis of solid acid catalysts in the solution or gas phase. 18 Various solid acid catalysts i.e., sulfated ZrO2 or Fe2O3, 19-20 sulfated Al2O3– * E-Mail: draayesha@gmail.com