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The protocol provides access to structurally diverse spiro-cyclopropane-pyrazolone derivatives bearing three contiguous stereogenic centers in good to excellent diastereoselectivities and excellent enantioselectivities. Mechanistic studies support the proposed reaction pathway, while the scalability of the reaction further demonstrates its practical utility.<\/jats:p>","DOI":"10.1021\/acs.orglett.6c03344","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T04:24:53Z","timestamp":1788495893000},"page":"11695-11700","source":"Crossref","is-referenced-by-count":1,"title":["Organocatalytic\nAsymmetric Formal [2 + 1] Cycloaddition\nReactions for the Synthesis of Spiro-cyclopropane-pyrazolones"],"prefix":"10.1021","volume":"28","author":[{"given":"Khushboo","family":"Gupta","sequence":"first","affiliation":[{"name":"Indian Institute of Technology Kanpur , , , ,","place":["Kanpur, Uttar Pradesh, India, 208 016"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chhavi","family":"Khajuria","sequence":"additional","affiliation":[{"name":"Indian Institute of Technology Kanpur , , , ,","place":["Kanpur, Uttar Pradesh, India, 208 016"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nidhi","family":"Saini","sequence":"additional","affiliation":[{"name":"Indian Institute of Technology Kanpur , , , ,","place":["Kanpur, Uttar Pradesh, India, 208 016"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0928-5543","authenticated-orcid":true,"given":"Vinod K.","family":"Singh","sequence":"additional","affiliation":[{"name":"Indian Institute of Technology Kanpur , , , ,","place":["Kanpur, Uttar Pradesh, India, 208 016"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,3]]},"reference":[{"key":"2026091809421493700_cit1a","volume-title":"Advances in\nNitrogen Heterocycles","author":"Moody","year":"1999"},{"key":"2026091809421493700_cit1b","doi-asserted-by":"publisher","DOI":"10.1002\/9781119708841","volume-title":"Synthetic Approaches to Nonaromatic\nNitrogen Heterocycles","author":"Faisca Phillips","year":"2021"},{"key":"2026091809421493700_cit1c","doi-asserted-by":"publisher","DOI":"10.1002\/9783527625505","volume-title":"Asymmetric Synthesis of Nitrogen Heterocycles","author":"Royer","year":"2009"},{"key":"2026091809421493700_cit2a","doi-asserted-by":"publisher","first-page":"2339","DOI":"10.1021\/acs.jmedchem.0c01786","article-title":"U.S. FDA Approved\nDrugs from 2015\u2013June 2020: A Perspective","volume":"64","author":"Bhutani","year":"2021","journal-title":"J. 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