title: Design, Synthesis, and Structural Analysis of Divalent N(I) Compounds and Identification of a New Electron-Donating Ligand.
abstract: The dative-bond representation (L→E) in compounds with main group elements (E) has triggered extensive debate in the recent past. The scope and limits of this nonclassical coordination bond warrant comprehensive exploration. Particularly compounds with (L→N←L')(+) arrangement are of special interest because of their therapeutic importance. This work reports the design and synthesis of novel chemical species with the general structural formula (L→N←L')(+) carrying the unusual ligand cyclohexa-2,5-diene-4-(diaminomethynyl)-1-ylidene. Four species belonging to the (L→N←L')(+) class carrying this unconventional ligand were synthesized. Quantum chemical and X-ray diffraction analyses showed that the electronic and geometric parameters are consistent with those of already reported divalent N(I) compounds. The molecular orbital analysis, geometric parameters, and spectral data clearly support the L→N and N←L' interactions in these species. The newly identified ligand has the properties of a reactive carbene and high nucleophilicity.
authors.affiliation: Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India. pvbharatam@niper.ac.in.
authors.forename: Prasad V
authors.initials: PV
authors.lastname: Bharatam
authors.affiliation: Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India.
authors.forename: Minhajul
authors.initials: M
authors.lastname: Arfeen
authors.affiliation: Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India.
authors.forename: Neha
authors.initials: N
authors.lastname: Patel
authors.affiliation: Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Jain
authors.affiliation: Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India.
authors.forename: Sonam
authors.initials: S
authors.lastname: Bhatia
authors.affiliation: Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar -, 160 062, Punjab, India. akchakraborti@niper.ac.in.
authors.forename: Asit K
authors.initials: AK
authors.lastname: Chakraborti
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Mohali, Sector 81, S.A.S. Nagar -, 140 308, Punjab, India.
authors.forename: Sadhika
authors.initials: S
authors.lastname: Khullar
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Mohali, Sector 81, S.A.S. Nagar -, 140 308, Punjab, India.
authors.forename: Vijay
authors.initials: V
authors.lastname: Gupta
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Mohali, Sector 81, S.A.S. Nagar -, 140 308, Punjab, India. sanjaymandal@iisermohali.ac.in.
authors.forename: Sanjay K
authors.initials: SK
authors.lastname: Mandal
keywords: carbene ligands; density functional calculations; ligand design; nitrogen