{"doi":"10.1002/poc.1670","title":"A design to prevent floating within the <i>N</i> scale of nucleophilicity","abstract":"<jats:title>Abstract</jats:title><jats:p>Two nucleophilicity scales (<jats:italic>N</jats:italic>′ and <jats:italic>N</jats:italic>″) including 96 nucleophiles, spanning 10<jats:sup>17</jats:sup> in rate constant, have been constructed directly from experimental rate constants for reactions of nucleophiles with dianisyl (log <jats:italic>k</jats:italic> = <jats:italic>N</jats:italic>′) or dimethylaminobenzhydrylium (log <jats:italic>k</jats:italic> = <jats:italic>N</jats:italic>″) cations in dichloromethane at 20 °C. The two scales are linked/unified by the formula: <jats:italic>N</jats:italic>′ − <jats:italic>N</jats:italic>″ = 6.6. In contrast, published procedures (H. Mayr <jats:italic>et al.</jats:italic> J. Am. Chem. Soc. 2001, <jats:italic>123</jats:italic>, 9500, and later work) involve 23 benzhydrylium cations and over 200 adjustable parameters obtained from the equation log <jats:italic>k</jats:italic> = <jats:italic>s</jats:italic>(<jats:italic>E</jats:italic> + <jats:italic>N</jats:italic>), where <jats:italic>k</jats:italic> is the rate constant, <jats:italic>E</jats:italic> is an electrophilicity parameter and <jats:italic>s</jats:italic> is a nucleophile‐specific sensitivity parameter. The definitions of <jats:italic>N</jats:italic>′ and <jats:italic>N</jats:italic>″ avoid a floating <jats:italic>N</jats:italic> scale, i.e. having less than the usual attachment to fixed reference points. New equations, log <jats:italic>k</jats:italic> = (<jats:italic>E</jats:italic> + <jats:italic>sN</jats:italic>′) or log <jats:italic>k</jats:italic> = (<jats:italic>E</jats:italic> + <jats:italic>sN</jats:italic>″), where <jats:italic>s</jats:italic> is now an electrophile‐specific parameter, are then used to correlate over 350 second‐order rate constants for reactions of other benzhydrylium cations with nucleophiles. For weaker, less polar, nucleophiles, <jats:italic>s</jats:italic> ∼ 1 and the new <jats:italic>E</jats:italic> and <jats:italic>N</jats:italic>′ parameters are in satisfactory agreement with published data for <jats:italic>E</jats:italic> and <jats:italic>N</jats:italic>. For more polar nucleophiles, <jats:italic>s</jats:italic> ≠ 1 and values of <jats:italic>N</jats:italic> − <jats:italic>N</jats:italic>″ vary by five log units. Copyright © 2010 John Wiley &amp; Sons, Ltd.</jats:p>","journal":"Journal of Physical Organic Chemistry","year":2010,"id":590728,"datarank":0.7899145274452857,"base_score":2.70805020110221,"endowment":2.70805020110221,"self_citation_contribution":0.40620753016533157,"citation_network_contribution":0.38370699727995417,"self_endowment_contribution":0.40620753016533157,"citer_contribution":0.38370699727995417,"corpus_percentile":null,"corpus_rank":null,"citation_count":14,"citer_count":8,"citers_with_citation_signal":5,"citers_with_endowment":5,"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":1511343,"name":"T. William Bentley","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"A design to prevent floating within the <i>N</i> scale of nucleophilicity","abstract":"<jats:title>Abstract</jats:title><jats:p>Two nucleophilicity scales (<jats:italic>N</jats:italic>′ and <jats:italic>N</jats:italic>″) including 96 nucleophiles, spanning 10<jats:sup>17</jats:sup> in rate constant, have been constructed directly from experimental rate constants for reactions of nucleophiles with dianisyl (log <jats:italic>k</jats:italic> = <jats:italic>N</jats:italic>′) or dimethylaminobenzhydrylium (log <jats:italic>k</jats:italic> = <jats:italic>N</jats:italic>″) cations in dichloromethane at 20 °C. The two scales are linked/unified by the formula: <jats:italic>N</jats:italic>′ − <jats:italic>N</jats:italic>″ = 6.6. In contrast, published procedures (H. Mayr <jats:italic>et al.</jats:italic> J. Am. Chem. Soc. 2001, <jats:italic>123</jats:italic>, 9500, and later work) involve 23 benzhydrylium cations and over 200 adjustable parameters obtained from the equation log <jats:italic>k</jats:italic> = <jats:italic>s</jats:italic>(<jats:italic>E</jats:italic> + <jats:italic>N</jats:italic>), where <jats:italic>k</jats:italic> is the rate constant, <jats:italic>E</jats:italic> is an electrophilicity parameter and <jats:italic>s</jats:italic> is a nucleophile‐specific sensitivity parameter. The definitions of <jats:italic>N</jats:italic>′ and <jats:italic>N</jats:italic>″ avoid a floating <jats:italic>N</jats:italic> scale, i.e. having less than the usual attachment to fixed reference points. New equations, log <jats:italic>k</jats:italic> = (<jats:italic>E</jats:italic> + <jats:italic>sN</jats:italic>′) or log <jats:italic>k</jats:italic> = (<jats:italic>E</jats:italic> + <jats:italic>sN</jats:italic>″), where <jats:italic>s</jats:italic> is now an electrophile‐specific parameter, are then used to correlate over 350 second‐order rate constants for reactions of other benzhydrylium cations with nucleophiles. For weaker, less polar, nucleophiles, <jats:italic>s</jats:italic> ∼ 1 and the new <jats:italic>E</jats:italic> and <jats:italic>N</jats:italic>′ parameters are in satisfactory agreement with published data for <jats:italic>E</jats:italic> and <jats:italic>N</jats:italic>. For more polar nucleophiles, <jats:italic>s</jats:italic> ≠ 1 and values of <jats:italic>N</jats:italic> − <jats:italic>N</jats:italic>″ vary by five log units. Copyright © 2010 John Wiley &amp; Sons, Ltd.</jats:p>","is_dataset_classified":null,"base_score":2.70805020110221,"endowment":2.70805020110221,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"20725694","pmcid":null,"openalex_id":"https://openalex.org/W2062845181","authors":[],"funders":[],"total_grants":0,"fwci":1.8398,"citation_percentile":0.83998971,"influential_citations":0,"citation_trend":[{"year":2012,"count":3},{"year":2013,"count":1},{"year":2015,"count":1},{"year":2016,"count":2}],"oa_status":"closed","license":"http://onlinelibrary.wiley.com/termsAndConditions#vor","oa_locations":[{"url":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fpoc.1670","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1002/poc.1670","host_type":"publisher"},{"url":"https://doi.org/10.1002/poc.1670","host_type":"journal"}],"fields_of_study":["Chemical Reaction Mechanisms","Organic and Inorganic Chemical Reactions","Organic Chemistry Cycloaddition Reactions"],"mesh_terms":[],"keywords":["Nucleophile","Chemistry","Electrophile","Reaction rate constant","Dichloromethane","Polar","Order (exchange)","Computational chemistry","Medicinal chemistry","Stereochemistry","Kinetics","Organic chemistry","Physics","Solvent","Catalysis","Quantum mechanics"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-07-25T11:02:04.962955Z","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":[]}