{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T20:44:47Z","timestamp":1775594687913,"version":"3.50.1"},"reference-count":58,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2002,6,10]],"date-time":"2002-06-10T00:00:00Z","timestamp":1023667200000},"content-version":"vor","delay-in-days":40,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["The Chemical Record"],"published-print":{"date-parts":[[2002,5]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>The Lewis acid\u2013assisted chiral Br\u00f8nsted acids (chiral LBAs), which are prepared from tin tetrachloride and optically active binaphthol derivatives, are highly effective chiral proton donor reagents for enantioselective protonation and biomimetic polyene cyclization. These chiral LBAs can directly protonate various silyl enol ethers and ketene disilyl acetals to give the corresponding \u03b1\u2010aryl or \u03b1\u2010halo ketones and \u03b1\u2010arylcarboxylic acids, respectively, with high enantiomeric excess (up to 98% ee). A catalytic version of enantioselective protonation was also achieved using stoichiometric amounts of 2,6\u2010dimethylphenol and catalytic amounts of monomethyl ether of optically active binaphthol in the presence of tin tetrachloride. The biomimetic cyclization of simple isoprenoids to polycyclic isoprenoids using chiral LBA is also described. This is the first example of a chiral Br\u00f8nsted acid\u2013induced enantioselective ene cyclization in synthetic chemistry. Geranyl phenyl ethers, <jats:italic>o<\/jats:italic>\u2010geranylphenols, and homogeranylphenol derivatives were directly cyclized in the presence of (<jats:italic>R<\/jats:italic>)\u2010binaphthol derivatives and tin tetrachloride (up to 90% ee). Compounds bearing a farnesyl group could also be cyclized under the same conditions to give the natural products (\u2212)\u2010ambrox<jats:sup>\u00ae<\/jats:sup> and (\u2212)\u2010chromazonarol, and (\u2212)\u2010tetracyclic polyprenoids of sedimentary origin. These chiral LBAs recognize the prochiral face of a trisubstituted terminal olefin and site selectively generate carbocations on the substrates. \u00a9 2002 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 2: 177\u2013188,2002: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002\/tcr.10020<\/jats:p>","DOI":"10.1002\/tcr.10020","type":"journal-article","created":{"date-parts":[[2002,10,6]],"date-time":"2002-10-06T12:29:56Z","timestamp":1033907396000},"page":"177-188","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":65,"title":["Chiral Proton Donor Reagents: Tin Tetrachloride\u2014Coordinated Optically Active Binaphthol Derivatives"],"prefix":"10.1002","volume":"2","author":[{"given":"Hideaki","family":"Ishibashi","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kazuaki","family":"Ishihara","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hisashi","family":"Yamamoto","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2002,6,10]]},"reference":[{"key":"e_1_2_8_2_2","volume-title":"Comprehensive Natural Products Chemistry, Vol. 5: Enzymes, Enzyme Mechanisms, Proteins, and Aspects of NO Chemistry","author":"Derek D.","year":"1999"},{"key":"e_1_2_8_3_2","volume-title":"Comprehensive Natural Products Chemistry, Vol. 2: Isoprenoids Including Cartenoids and Steroids","author":"Derek D.","year":"1999"},{"key":"e_1_2_8_4_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00103a052"},{"key":"e_1_2_8_5_2","first-page":"513","volume":"69","author":"Ishihara K.","year":"1996","journal-title":"Croat Chem Acta"},{"key":"e_1_2_8_6_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja962414r"},{"key":"e_1_2_8_7_2","doi-asserted-by":"publisher","DOI":"10.1055\/s-1997-5758"},{"key":"e_1_2_8_8_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja001164i"},{"key":"e_1_2_8_9_2","first-page":"4907","volume":"121","author":"Ishihara K.","year":"1999","journal-title":"J Am Chem Soc"},{"key":"e_1_2_8_10_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja001165a"},{"key":"e_1_2_8_11_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja003541x"},{"key":"e_1_2_8_12_2","author":"Ishihara K.","year":"2002","journal-title":"J Am Chem Soc"},{"key":"e_1_2_8_13_2","first-page":"3851","volume-title":"Methods of Organic Chemistry","author":"Helmchen G.","year":"1995"},{"key":"e_1_2_8_14_2","doi-asserted-by":"publisher","DOI":"10.1002\/anie.199625661"},{"key":"e_1_2_8_15_2","doi-asserted-by":"publisher","DOI":"10.1055\/s-1997-6131"},{"key":"e_1_2_8_16_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00084a080"},{"key":"e_1_2_8_17_2","doi-asserted-by":"publisher","DOI":"10.1002\/anie.199401071"},{"key":"e_1_2_8_18_2","doi-asserted-by":"publisher","DOI":"10.1021\/jo00112a002"},{"key":"e_1_2_8_19_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00108a005"},{"key":"e_1_2_8_20_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0957-4166(97)00423-0"},{"key":"e_1_2_8_21_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0040-4039(97)01705-X"},{"key":"e_1_2_8_22_2","doi-asserted-by":"publisher","DOI":"10.1039\/a704779g"},{"key":"e_1_2_8_23_2","doi-asserted-by":"publisher","DOI":"10.1039\/a803756f"},{"key":"e_1_2_8_24_2","doi-asserted-by":"publisher","DOI":"10.1055\/s-1998-1594"},{"key":"e_1_2_8_25_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0040-4020(98)00482-7"},{"key":"e_1_2_8_26_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0957-4166(98)00228-6"},{"key":"e_1_2_8_27_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0040-4039(99)00615-2"},{"key":"e_1_2_8_28_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0040-4020(99)00143-X"},{"key":"e_1_2_8_29_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00182a020"},{"key":"e_1_2_8_30_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0040-4039(00)60975-9"},{"key":"e_1_2_8_31_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0957-4166(00)86269-2"},{"key":"e_1_2_8_32_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00022a054"},{"key":"e_1_2_8_33_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0957-4166(00)82229-6"},{"key":"e_1_2_8_34_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0040-4039(00)76652-4"},{"key":"e_1_2_8_35_2","doi-asserted-by":"publisher","DOI":"10.1002\/anie.199404751"},{"key":"e_1_2_8_36_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00104a008"},{"key":"e_1_2_8_37_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00117a051"},{"key":"e_1_2_8_38_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00538a023"},{"key":"e_1_2_8_39_2","doi-asserted-by":"publisher","DOI":"10.1021\/cr00022a009"},{"key":"e_1_2_8_40_2","doi-asserted-by":"publisher","DOI":"10.1021\/cr00013a014"},{"key":"e_1_2_8_41_2","doi-asserted-by":"publisher","DOI":"10.1021\/bi00202a004"},{"key":"e_1_2_8_42_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.277.5333.1820"},{"key":"e_1_2_8_43_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.277.5333.1815"},{"key":"e_1_2_8_44_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.277.5333.1811"},{"key":"e_1_2_8_45_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja01104a535"},{"key":"e_1_2_8_46_2","doi-asserted-by":"publisher","DOI":"10.1002\/hlca.19550380728"},{"key":"e_1_2_8_47_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja01624a038"},{"key":"e_1_2_8_48_2","doi-asserted-by":"publisher","DOI":"10.1351\/pac198153061259"},{"key":"e_1_2_8_49_2","first-page":"47","author":"Johnson W.S.","year":"1991","journal-title":"Tetrahedron"},{"key":"e_1_2_8_50_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0040-4039(97)01488-3"},{"key":"e_1_2_8_51_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja00203a012"},{"key":"e_1_2_8_52_2","doi-asserted-by":"publisher","DOI":"10.1016\/0040-4020(89)80017-1"},{"key":"e_1_2_8_53_2","doi-asserted-by":"publisher","DOI":"10.1021\/jo9812936"},{"key":"e_1_2_8_54_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja01018a051"},{"key":"e_1_2_8_55_2","doi-asserted-by":"publisher","DOI":"10.1038\/385613a0"},{"key":"e_1_2_8_56_2","volume-title":"NBO 4.0","author":"Glendening E.D.","year":"1996"},{"key":"e_1_2_8_57_2","doi-asserted-by":"publisher","DOI":"10.1063\/1.1674408"},{"key":"e_1_2_8_58_2","doi-asserted-by":"publisher","DOI":"10.1063\/1.448800"},{"key":"e_1_2_8_59_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.271.5246.163"}],"container-title":["The Chemical Record"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Ftcr.10020","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/tcr.10020","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,7]],"date-time":"2023-10-07T07:32:58Z","timestamp":1696663978000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/tcr.10020"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2002,5]]},"references-count":58,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2002,5]]}},"alternative-id":["10.1002\/tcr.10020"],"URL":"https:\/\/doi.org\/10.1002\/tcr.10020","archive":["Portico"],"relation":{},"ISSN":["1527-8999","1528-0691"],"issn-type":[{"value":"1527-8999","type":"print"},{"value":"1528-0691","type":"electronic"}],"subject":[],"published":{"date-parts":[[2002,5]]},"assertion":[{"value":"2002-01-10","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2002-02-07","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2002-06-10","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}