{"doi":"10.3390/molecules30122610","title":"A Case of Competitive Aromatization vs. Sigmatropic [1,5]-Hydrogen Atom Migration in a 1,2,4-Cyclohexatriene Intermediate Derived from a Bis-Enyne Cyclization","abstract":"1,2,4-Cyclohexatrienes are strained, reactive intermediates often formed by the tetradehydro-Diels-Alder (TDDA) reaction of a conjugated enyne bearing a tethered alkyne as the enynophile. The ene component is commonly the π-bond of an aromatic group. In this focused study, we investigated the reactivity of a symmetrical substrate in which the pair of terminal ene moieties were simple 2-propenyl groups. The intermediate 1,2,4-cyclohexatriene, now bearing a 5-isopropenyl group, underwent competitive aromatization (the most usual outcome of the strain-relieving event of the cyclohexatriene), along with an intramolecular [1,5]-hydrogen atom migration, ultimately producing a non-benzenoid, pyrrole derivative. This represents a previously unknown process for a 1,2,4-cyclohexatriene derivative. Mechanistic aspects of the competitive processes were revealed by experiments performed in the presence of various protic additives (MeOD and BHT).","journal":"Molecules","year":2025,"id":568590,"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":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9531,"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":903825,"name":"Qian Xu","orcid":"0000-0002-8655-8683","position":1,"is_corresponding":false},{"id":369512,"name":"Thomas R. Hoye","orcid":"0000-0001-9318-1477","position":2,"is_corresponding":false},{"id":1473455,"name":"Reginald Tang","orcid":"0009-0000-7982-3568","position":0,"is_corresponding":true}],"reference_count":27,"raw_metadata":null,"created_at":"2026-07-19T02:56:55.795846Z","pmid":"40572572","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":[]}