{"doi":"10.1021/jacs.5c02735","title":"Divergent Kinetic/Thermodynamic Selectivity in Palladium(II)-Mediated C–H Activation to Form 5- and 6-Membered Palladacycles","abstract":"Palladium-catalyzed C–H functionalization proceeds via metallacycle formation and often favors 6-membered palladacycles, contrasting the typical preference for 5-membered chelates in transition-metal complexes. The present study probes the origin of this behavior by comparing the reactivity of benzoate and phenylacetate substrates in stoichiometric and catalytic reactions with MPAA-ligated Pd(OAc) 2 (MPAA = mono- N -protected amino acid). Stoichiometric competition studies show that 6-membered palladacycle formation is kinetically favored, while the 5-membered palladacycle is thermodynamically favored. Density functional theory (DFT) calculations reveal that the transition state for 5-membered palladacycle formation is inhibited by a higher distortion energy. Replacement of the α-MPAA ligand with a more flexible β-MPAA derivative lowers the transition state energy of benzoate C–H activation and improves the catalytic performance.","journal":"Journal of the American Chemical Society","year":2025,"id":519868,"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":6,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9442,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1149218,"name":"Kyana M. Sanders","orcid":"0000-0003-3483-6992","position":1,"is_corresponding":false},{"id":251447,"name":"Ilia A. Guzei","orcid":"0000-0003-1976-7386","position":2,"is_corresponding":false},{"id":305804,"name":"Djamaladdin G. Musaev","orcid":"0000-0003-1160-6131","position":3,"is_corresponding":false},{"id":110277,"name":"Shannon S. Stahl","orcid":"0000-0002-9000-7665","position":4,"is_corresponding":false},{"id":306706,"name":"Philip S. Zhou","orcid":null,"position":0,"is_corresponding":true}],"reference_count":45,"raw_metadata":null,"created_at":"2026-07-19T02:49:23.618703Z","pmid":"40663506","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":[]}