Synlett 2007(9): 1371-1374  
DOI: 10.1055/s-2007-980361
LETTER
© Georg Thieme Verlag Stuttgart · New York

Copper(II) Acetate Mediated Reactions of Methylenecyclopropane and Diphenyl Diselenide

Lei Yua, Xian Huang*,a,b
a Department of Chemistry, Zhejiang University (Campus Xixi), Hangzhou 310028, P. R. of China
b State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. of China
Fax: +86(571)88807077; e-Mail: huangx@mail.hz.zj.cn;
Further Information

Publication History

Received 20 December 2006
Publication Date:
23 May 2007 (online)

Abstract

Phenylselenyl-substituted cyclobutenes and 1,3-butadienes were obtained from a copper(II) acetate mediated reaction between methylenecyclopropanes and diphenyl diselenide.

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2-Phenylselenyl-3,3-diarylcyclobutene (6), typical procedure: Under an N2 atmosphere, a solution of diphenylmethylenecyclopropane (1a, 0.062 g, 0.3 mmol), diphenyl diselenide (0.094 g, 0.3 mmol) and Cu(OAc)2 (0.060 g, 0.3 mmol) in AcOH (2 mL) was irradiated with a tungsten lamp (300 W). The temperature rose to 40 °C because of the irradiation. The reaction was monitored by TLC (PE). When the reaction was complete, the solvent was evaporated under vacuum and the residue was subjected to preparative TLC (PE) to afford 6a in 65% yield. IR (KBr): 3055, 1575, 1491, 1217, 1025, 750, 696 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.22-7.60 (m, 15 H), 6.12 (t, J = 0.8 Hz, 1 H), 3.17 (d, J = 0.8 Hz, 2 H); 13C NMR (100 MHz, CDCl3): δ = 46.9, 61.9, 126.4, 127.4, 127.5, 128.0, 128.1, 129.3, 133.9, 134.8, 141.8, 144.1; MS (EI, 70 eV): m/z (%) = 362 (12) [M+], 281 (14), 205 (100); HRMS (EI): m/z calcd for C22H18Se: 362.0574; found: 362.0574.

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1,1-Diaryl-2-phenylselenylbuta-1,3-diene (11), typical procedure: Under an N2 atmosphere, a solution of diphenylmethylenecyclopropane (1a, 0.062 g, 0.3 mmol), diphenyl diselenide (0.094 g, 0.3 mmol) and Cu(OAc)2 (0.060 g, 0.3 mmol) in AcOH (0.2 mL) acid was stirred at 110 °C. The reaction was monitored by TLC (PE). When the reaction was complete, the solvent was evaporated under vacuum and the residue was subjected to preparative TLC (PE) to afford 11a in 68% yield. IR (film): 3054, 1576, 1477, 1440, 737, 697 cm-1; 1H NMR (400 MHz, CDCl3): δ = 7.14-7.34 (m, 15 H), 6.56-6.63 (m, 1 H), 5.81-5.85 (m, 1 H), 5.22-5.25 (m, 1 H); 13C NMR (100 MHz, CDCl3): δ = 120.9, 125.8, 127.3, 127.7, 128.1, 128.9, 129.4, 130.0, 130.1, 130.2, 133.0, 135.4, 141.6, 144.1, 151.6; MS (EI, 70 eV): m/z (%) = 362 (30) [M+], 281 (15), 205 (100); HRMS (EI): m/z calcd for C22H18Se: 362.0574; found: 362.0567.