{"doi":"10.1002/jccs.201400381","title":"The Substituent Effect of 1‐Arylazonaphthen‐2‐ols on Azo‐hydrazone Tautomerization According to NMR Analysis","abstract":"<jats:title>Abstract</jats:title><jats:p>The substituent effect on azo‐hydrazone tautomerization of 1‐arylazonaphthen‐ols is studied by means of NMR analysis. Among the <jats:sup>13</jats:sup>C chemical shifts, the C(2) of this series compound is the most sensitive to the variation in the nature of substituent on the phenyl ring. Therefore, the variation in the chemical shifts of C(2) is used to probe the substituent effect by using the substituent chemical shifts and free energy vs. Hammett’s constant (χρ<jats:sup>+</jats:sup>). Both methods give a negative correlation slope, indicating the electron‐with‐ drawing groups favor the hydrazone tautomer form. The effect on the chemical shifts of C(2) of compound <jats:bold>8</jats:bold> in ten solvents can be classified as the solvent with a proton‐donor, proton‐acceptor and arenes system. The substituent with electron‐donating character is more sensitive to the nature of solvent and it favors the hydrazone form. Free energy obtained from the dynamic NMR technique indicates the tautomerization favors the hydrazone‐form for the substituent with electron‐withdrawing character.</jats:p>","journal":"Journal of the Chinese Chemical Society","year":2015,"id":47138,"datarank":0.5129435750900423,"base_score":1.6094379124341003,"endowment":1.6094379124341003,"self_citation_contribution":0.24141568686511508,"citation_network_contribution":0.2715278882249272,"self_endowment_contribution":0.24141568686511508,"citer_contribution":0.2715278882249272,"corpus_percentile":null,"corpus_rank":null,"citation_count":4,"citer_count":4,"citers_with_citation_signal":4,"citers_with_endowment":4,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":217632,"name":"Chien‐Chih Chen","orcid":null,"position":1,"is_corresponding":false},{"id":217633,"name":"Mei‐Fan Ding","orcid":null,"position":2,"is_corresponding":false},{"id":217634,"name":"Shaw‐Tao Lin","orcid":null,"position":3,"is_corresponding":false},{"id":217631,"name":"Yi‐Cang Lin","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"The Substituent Effect of 1‐Arylazonaphthen‐2‐ols on Azo‐hydrazone Tautomerization According to NMR Analysis","abstract":"<jats:title>Abstract</jats:title><jats:p>The substituent effect on azo‐hydrazone tautomerization of 1‐arylazonaphthen‐ols is studied by means of NMR analysis. Among the <jats:sup>13</jats:sup>C chemical shifts, the C(2) of this series compound is the most sensitive to the variation in the nature of substituent on the phenyl ring. Therefore, the variation in the chemical shifts of C(2) is used to probe the substituent effect by using the substituent chemical shifts and free energy vs. Hammett’s constant (χρ<jats:sup>+</jats:sup>). Both methods give a negative correlation slope, indicating the electron‐with‐ drawing groups favor the hydrazone tautomer form. The effect on the chemical shifts of C(2) of compound <jats:bold>8</jats:bold> in ten solvents can be classified as the solvent with a proton‐donor, proton‐acceptor and arenes system. The substituent with electron‐donating character is more sensitive to the nature of solvent and it favors the hydrazone form. Free energy obtained from the dynamic NMR technique indicates the tautomerization favors the hydrazone‐form for the substituent with electron‐withdrawing character.</jats:p>","is_dataset_classified":null,"base_score":1.6094379124341003,"endowment":1.6094379124341003,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"18998783","pmcid":null,"openalex_id":"https://openalex.org/W2030867282","authors":[],"funders":[],"total_grants":0,"fwci":0.0,"citation_percentile":0.04162928,"influential_citations":0,"citation_trend":[{"year":2021,"count":2},{"year":2022,"count":1},{"year":2023,"count":1}],"oa_status":"closed","license":"http://onlinelibrary.wiley.com/termsAndConditions#vor","oa_locations":[{"url":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjccs.201400381","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1002/jccs.201400381","host_type":"publisher"},{"url":"https://doi.org/10.1002/jccs.201400381","host_type":"journal"}],"fields_of_study":["Synthesis and Characterization of Heterocyclic Compounds","Chemical Reaction Mechanisms","Axial and Atropisomeric Chirality Synthesis","Chemistry"],"mesh_terms":[],"keywords":["Substituent","Hydrazone","Chemistry","Tautomer","Chemical shift","Computational chemistry","Hammett equation","Proton NMR","Carbon-13 NMR","Stereochemistry","Reaction rate constant","Physical chemistry","Kinetics"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Affordable and clean energy"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-07-17T05:08:12.019284Z","pmid":null,"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":[]}