{"doi":"10.1021/acs.inorgchem.2c03484","title":"Oxygen versus Sulfur Coordination in Cobalt Superoxo Complexes: Spectroscopic Properties, O<sub>2</sub> Binding, and H-Atom Abstraction Reactivity","abstract":"A five-coordinate, disiloxide-ligated cobalt(II) (S = 3/2) complex (1) was prepared as an oxygen-ligated analogue to the previously reported silanedithiolate-ligated CoII(Me3TACN)(S2SiMe2) (J. Am. Chem. Soc., 2019, 141, 3641–3653). The structural and spectroscopic properties of 1 were analyzed by single-crystal X-ray diffraction, electron paramagnetic resonance (EPR), and NMR spectroscopies. The reactivity of 1 with dioxygen was examined, and it was shown to bind O2 reversibly in a range of solvents at low temperatures. A cobalt(III)–superoxo complex, CoIII(O2·–)(Me3TACN)((OSi2Ph)2O) (2), was generated, and was analyzed by UV–vis, EPR, and resonance Raman spectroscopies. Unlike its sulfur-ligated analogue, complex 2 can thermally release O2 to regenerate 1. Vibrational assignments for selective 18O isotopic labeling of both O2 and disiloxide ligands in 2 are consistent with a 6-coordinate, Co(η1–O2·–)(“end-on”) complex. Complex 2 reacts with the O–H bond of 4-methoxy-2,2,6,6-tetramethylpiperidin-1-ol (4-MeO-TEMPOH) via H-atom abstraction with a rate of 0.58(2) M–1 s–1 at −105 °C, but it is unable to oxidize phenol substrates. This bracketed reactivity suggests that the O–H bond being formed in the putative CoIII(OOH) product has a relatively weak O–H bond strength (BDFE ∼66–74 kcal mol–1). These thermodynamic and kinetic parameters are similar to those seen for the sulfur-ligated Co(O2)(Me3TACN)(S2SiMe2), indicating that the differences in the electronic structure for O versus S ligation do not have a large impact on H-atom abstraction reactivity.","journal":"Inorganic Chemistry","year":2022,"id":287946,"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":3,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9515,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":719339,"name":"Therese Albert","orcid":"0000-0001-7248-0873","position":1,"is_corresponding":false},{"id":968389,"name":"Sudha Yadav","orcid":"0000-0002-5542-1078","position":2,"is_corresponding":false},{"id":968390,"name":"Jithin Thomas","orcid":"0000-0001-7931-0850","position":3,"is_corresponding":false},{"id":414296,"name":"Maxime A. Siegler","orcid":"0000-0003-4165-7810","position":4,"is_corresponding":false},{"id":588284,"name":"Pierre Moënne‐Loccoz","orcid":"0000-0002-7684-7617","position":5,"is_corresponding":false},{"id":719341,"name":"David P. Goldberg","orcid":"0000-0003-4645-1045","position":6,"is_corresponding":false},{"id":719338,"name":"Jesse B. Gordon","orcid":"0000-0002-6331-7940","position":0,"is_corresponding":true}],"reference_count":68,"raw_metadata":null,"created_at":"2026-07-19T00:30:11.069895Z","pmid":"36538786","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":[]}