Synlett, Table of Contents Synlett 2017; 28(18): 2478-2482DOI: 10.1055/s-0036-1588451 cluster © Georg Thieme Verlag Stuttgart · New YorkReactivity of Seven-Membered-Ring trans-Alkenes with Electrophiles Jillian R. Sanzone Department of Chemistry, New York University, 100 Washington Square East, New York, NY 10003, USA Email: kwoerpel@nyu.edu , K. A. Woerpel * Department of Chemistry, New York University, 100 Washington Square East, New York, NY 10003, USA Email: kwoerpel@nyu.edu› Author AffiliationsRecommend Article Abstract Buy Article All articles of this category Published as part of the Cluster Silicon in Synthesis and Catalysis Abstract Seven-membered-ring trans-alkenes containing a silicon–oxygen bond reacted rapidly with oxygen gas and electron-deficient alkenes and alkynes to give products with high selectivity. Addition of an electron-donating substituent or incorporating additional strain increased the reactivity by over two orders of magnitude. These results indicate that release of strain is not the only driving force for reactivity. Key words Key wordsalkenes - conjugate addition - cycloheptene - strained molecules - silicon Full Text References References and Notes 1 Corey EJ. Carey FA. Winter RA. E. J. Am. Chem. Soc. 1965; 87: 934 2 Ziegler K. Wilms H. Justus Liebigs Ann. Chem. 1950; 567: 1 3 Inoue Y. Ueoka T. Kuroda T. Hakushi T. J. Chem. Soc., Perkin Trans. 2 1983; 983 4 Greene MA. Prévost M. Tolopilo J. Woerpel KA. J. Am. Chem. Soc. 2012; 134: 12482 5 Hurlocker B. Hu C. Woerpel KA. Angew. Chem. Int. Ed. 2015; 54: 4295 6 Hoffmann R. Inoue Y. J. Am. Chem. Soc. 1999; 121: 10702 7 Shea KJ. Kim J.-S. J. Am. Chem. Soc. 1992; 114: 3044 8 Inoue Y. Turro NJ. Tetrahedron Lett. 1980; 21: 4327 9 Squillacote M. Mooney M. De Felippis J. J. Am. Chem. Soc. 1990; 112: 5364 10 Poon TH. W. Park SH. Elemes Y. Foote CS. J. Am. Chem. Soc. 1995; 117: 10468 11 Corey EJ. Tada M. LaMahieu R. Libit L. J. Am. Chem. 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Purification by flash chromatography (EtOAc–hexanes = 2:98) afforded ketone 4 as a white solid (0.025 g, 59% over three steps): mp 94–95 °C. 1H NMR (600 MHz, CDCl3): δ = 7.36–7.27 (m, 5 H), 4.97 (d, J = 9.7 Hz, 1 H), 4.72 (dd, J = 10.0, 4.9 Hz, 1 H), 2.86 (dq, J = 9.7, 7.0 Hz, 1 H), 1.21 (dd, J = 14.5, 4.9 Hz, 1 H), 1.12–1.10 (m, 1 H), 1.05 (s, 9 H), 0.93 (s, 9 H), 0.77 (d, J = 7.0 Hz, 3 H), 0.16 (s, 9 H). 13C NMR (125 MHz, CDCl3): δ = 215.1 (C), 142.6 (C), 128.4 (CH), 127.9 (CH), 126.8 (CH), 78.7 (CH), 77.6 (CH), 56.3 (CH), 28.0 (CH3), 27.6 (CH3), 21.7 (C), 20.8 (C), 16.6 (CH2), 14.4 (CH3), 0.1 (CH3). IR (ATR): 1708, 1071, 838 cm–1. ESI-HRMS: m/z calcd for C23H40NaO3Si2 [M + Na]+: 443.2408; found: 443.2410. Anal. Calcd for C23H40O3Si2: C, 65.66; H, 9.58. Found: C, 65.94; 9.33. 28 Warmuth R. Marvel MA. Chem. Eur. J. 2001; 7: 1209 29 Rubottom GM. Vazquez MA. Pelegrina DR. Tetrahedron Lett. 1974; 15: 4319 30 Bartlett PD. Banavali R. J. Org. Chem. 1991; 56: 6043 31 Clark KB. Howard JA. 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