Structure and Reactivity of a Copper(I)-Fused N-Heterocyclic Carbene ­Complex: Reactivity toward Styrenic and Strained Alkenes

Abstract

The synthesis of a fused N-heterocyclic carbene complex is accomplished using a flow-chemistry approach where a fused N-herterocyclic imidazolium chloride is passed through a packed bed of copper(I) oxide. The identity of the resulting complex is confirmed via crystal structure, and the reactivity is examined in the context of alkene hydroboration. We demonstrate that this novel complex can perform the desired reaction whereas the carbene ­ligand alone cannot.

Key words

boron - copper - flow chemistry - N-heterocyclic carbene complex - catalytic hydroboration - strained alkenes

• References and Notes

• 1 These authors contributed equally.
• 2a Zhang S.-S, Zhao Y.-S, Tian P, Lin G.-Q. Synlett 2013; 24: 437
• 2b Park JK, Ondrusek BA, McQuade DT. Org. Lett. 2012; 14: 4790
• 2c Corberán R, Mszar NW, Hoveyda AH. Angew. Chem. Int. Ed. 2011; 50: 7079
• 2d Jang H, Zhugralin AR, Lee Y, Hoveyda AH. J. Am. Chem. Soc. 2011; 133: 7859
• 3a Hunter NM, Vogels CM, Decken A, Bell A, Westcott SA. Inorg. Chim. Acta 2011; 365: 408
• 3b Yamamoto Y, Fujikawa R, Umemoto T, Miyaura N. Tetrahedron 2004; 60: 10695
• 4a Pubill-Ulldemolins C, Poyatos M, Bo C, Fernandez E. Dalton Trans. 2013; 42: 746
• 4b Fritschi CB, Wernitz SM, Vogels CM, Shaver MP, Decken A, Bell A, Westcott SA. Eur. J. Inorg. Chem. 2008; 779
• 5a Ramírez J, Sanaú M, Fernández E. Angew. Chem. Int. Ed. 2008; 47: 5194
• 5b Ishiyama T, Yamamoto M, Miyaura N. Chem. Commun. 1997; 689
• 5c Beletskaya I, Pelter A. Tetrahedron 1997; 53: 4957
• 5d Iverson CN, Smith MR. Organometallics 1997; 16: 2757
• 5e Pereira S, Srebnik M. J. Am. Chem. Soc. 1996; 118: 909
• 5f Burgess K, Ohlmeyer MJ. Chem. Rev. 1991; 91: 1179
• 6 Lillo V, Fructos MR, Ramírez J, Braga AA. C, Maseras F, Díaz-Requejo MM, Pérez PJ, Fernández E. Chem. Eur. J. 2007; 13: 2614
• 7a Park JK, McQuade DT. Angew. Chem. Int. Ed. 2012; 51: 2717
• 7b Park JK, McQuade DT. Synthesis 2012; 44: 1485
• 7c Park JK, Lackey HH, Ondrusek BA, McQuade DT. J. Am. Chem. Soc. 2011; 133: 2410
• 7d Park JK, Lackey HH, Rexford MD, Kovnir K, Shatruk M, McQuade DT. Org. Lett. 2010; 12: 5008
• 8 Opalka SM, Park JK, Longstreet AR, McQuade DT. Org. Lett. 2013; 15: 996
• 9 Burstein C, Lehmann CW, Glorius F. Tetrahedron 2005; 61: 6207
• 10 Bonet A, Pubill-Ulldemolins C, Bo C, Gulyás H, Fernández E. Angew. Chem. Int. Ed. 2011; 50: 7158
• 11 The crystallographic data in cif format can be obtained from the Cambridge Crystallographic Data Centre upon quoting deposition number CCDC-890838.
• 12 Wu H, Radomkit S, O’Brien JM, Hoveyda AH. J. Am. Chem. Soc. 2012; 134: 8277