{"doi":"10.1021/jacs.0c02487","title":"Cp<sub>2</sub>Ti(κ<sup>2</sup><i>-</i><sup><i>t</i></sup>BuNCN<sup><i>t</i></sup>Bu): A Complex with an Unusual κ<sup>2</sup> Coordination Mode of a Heterocumulene Featuring a Free Carbene","abstract":"Although there are myriad binding modes of heterocumulenes to metal centers, the monometallic κ2-ECE (E = O, S, NR) coordination mode has not been reported. Herein, the synthesis, isolation, and physical characterization of Cp2Ti(κ2-tBuNCNtBu) (3) (Cp = cyclopentadienyl, tBu = tert-butyl), a strained 4-membered metallacycle bearing a free carbene, is described. Computational (DFT, CASSCF, QT-AIM, ELF) and solid-state CP-MAS 13C NMR spectroscopic analysis indicate that 3 is best described as a free carbene with partial Ti–Cβ bonding that results from Ti–N π-bonding mixing with N–C–N σ-bonding of the bent N–C–N framework. Reactivity studies of 3 corroborate its carbene-like nature: protonation with [LutH]I results in the formation of a Ti-formamidinate (4), while oxidation with S8 yields a Ti-thioureate (5). Additionally, a related bridged dititanamidocarbene, (Cp2Ti)2(μ-η1,η1-CyNCNCy) (10) (Cy = cyclohexyl) is reported. Taken together, this work suggests that the 2-electron reduction of heterocumulene moieties can allow access to unusual free carbene coordination geometries given the proper stabilizing coordination environment from the reducing transition metal fragment.","journal":"Journal of the American Chemical Society","year":2020,"id":94702,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":37,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9468,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2020-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":471535,"name":"Christopher P. Gordon","orcid":"0000-0002-2199-8995","position":1,"is_corresponding":false},{"id":296241,"name":"Robin P. Harkins","orcid":"0000-0002-1918-9814","position":2,"is_corresponding":false},{"id":471536,"name":"Meghan E. McGreal","orcid":"0000-0003-3191-625X","position":3,"is_corresponding":false},{"id":438427,"name":"Xuelan Wen","orcid":"0000-0002-7151-6157","position":4,"is_corresponding":false},{"id":471537,"name":"Christophe Copéret","orcid":"0000-0001-9660-3890","position":5,"is_corresponding":false},{"id":438430,"name":"Jason D. Goodpaster","orcid":"0000-0001-6461-4501","position":6,"is_corresponding":false},{"id":296244,"name":"Ian A. Tonks","orcid":"0000-0001-8451-8875","position":7,"is_corresponding":false},{"id":438426,"name":"Evan P. Beaumier","orcid":"0000-0003-3760-3879","position":0,"is_corresponding":true}],"reference_count":111,"raw_metadata":null,"created_at":"2026-07-18T22:33:00.770265Z","pmid":"32240590","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}