Synthesis of Siloles via Rhodium-Catalyzed Cyclization of Alkynes and Diynes with Hexamethyldisilane

Abstract

A rhodium-catalyzed silylative cyclization of alkynes and 1,6-diynes with hexamethyldisilane is described. These reactions enable the synthesis of densely substituted silole derivatives through the use of a rhodium(I)-norborna-2,5-diene complex as a catalyst.

Key words

alkynes - cyclization - diynes - rhodium - siloles

References and Notes

• 1a Dubac J. Laporterie A. Manuel G. Chem. Rev.  1990,  90:  215 
• 1b Hissler M. Dyer PW. Réau R. Coord. Chem. Rev.  2003,  244:  1 
• 1c Yamaguchi S. Tamao K. Chem. Lett.  2005,  34:  2 
• 2a Yamaguchi S. Tamao K. J. Chem. Soc., Dalton Trans.  1998,  3693 
• 2b Chen J. Cao Y. Macromol. Rapid Commun.  2007,  28:  1714 
• 2c Zhan X. Barlow S. Marder SR. Chem. Commun.  2009,  1948 
• 2d Liu J. Lam JWY. Tang BZ. J. Inorg. Organomet. Polym.  2009,  19:  249 
• 3a Matsuda T. Kadowaki S. Goya T. Murakami M. Org. Lett.  2007,  9:  133 
• 3b Matsuda T. Kadowaki S. Murakami M. Chem. Commun.  2007,  2627 
• 3c Matsuda T. Kadowaki S. Yamaguchi Y. Murakami M. Chem. Commun.  2008,  2744 
• 3d Matsuda T. Yamaguchi Y. Murakami M. Synlett  2008,  561 
• 3e Matsuda T. Yamaguchi Y. Murakami M. Synlett  2010,  2743 
• 4a Ohmura T. Masuda K. Suginome M. J. Am. Chem. Soc.  2008,  130:  1526 
• 4b Shimizu M. Mochida K. Hiyama T. Angew. Chem. Int. Ed.  2008,  47:  9760 
• 4c Tobisu M. Onoe M. Kita Y. Chatani N. J. Am. Chem. Soc.  2009,  131:  7506 
• 4d Ureshino T. Yoshida T. Kuninobu Y. Takai K. J. Am. Chem. Soc.  2010,  132:  14324 
• For earlier studies on catalytic construction of silole skeletons, see:
• 5a Okinoshima H. Yamamoto K. Kumada M. J. Am. Chem. Soc.  1972,  94:  9263 
• 5b Sakurai H. Kamiyama Y. Nakadaira Y. J. Am. Chem. Soc.  1977,  99:  3879 
• 5c Seyferth D. Vick SC. Shannon ML. Lim TFO. Duncan DP. J. Organomet. Chem.  1977,  135:  C37 
• 5d Schäfer A. Weidenbruch M. Pohl S. J. Organomet. Chem.  1985,  282:  305 
• 5e Ikenaga K. Hiramatsu K. Nasaka N. Matsumoto S. J. Org. Chem.  1993,  58:  5045 
• 5f Ojima I. Fracchiolla DA. Donovan RJ. Banerji P. J. Org. Chem.  1994,  59:  7594 
• 5g Palmer WS. Woerpel KA. Organometallics  1997,  16:  1097 
• For reviews, see:
• 6a Han L.-B. Tanaka M. Chem. Commun.  1999,  395 
• 6b Beletskaya I. Moberg C. Chem. Rev.  2006,  106:  2320 
• 6c Suginome M. Matsuda T. Ohmura T. Seki A. Murakami M. In Comprehensive Organometallic Chemistry III   Vol. 10:  Crabtree R. Mingos M. Ojima I. Elsevier; Oxford: 2007.  p.725 
• 7a Walter C. Auer G. Oestreich M. Angew. Chem. Int. Ed.  2006,  45:  5675 
• 7b Nakao Y. Chen J. Imanaka H. Hiyama T. Ichikawa Y. Duan W.-L. Shintani R. Hayashi T. J. Am. Chem. Soc.  2007,  129:  9137 
• 7c Walter C. Fröhlich R. Oestreich M. Tetrahedron  2009,  65:  5513 
• 8a Tobisu M. Kita Y. Chatani N. J. Am. Chem. Soc.  2006,  128:  8152 
• 8b Tobisu M. Ano Y. Chatani N. Chem. Asian J.  2008,  3:  1585 
• 8c Tobisu M. Kita Y. Ano Y. Chatani N. J. Am. Chem. Soc.  2008,  130:  15982 
• 8d Kita Y. Tobisu M. Chatani N. Org. Lett.  2010,  12:  1864 
• For Si-Me bond cleavage observed in palladium-catalyzed reactions, see:
• 10a Rauf W. Brown JM. Angew. Chem. Int. Ed.  2008,  47:  4228 
• 10b Nakao Y. Takeda M. Matsumoto T. Hiyama T. Angew. Chem. Int. Ed.  2010,  49:  4447 

9

The attempted detection of tetramethylsilane formation was unsuccessful when the reaction was performed in C₆D₆ at 30 ˚C in a sealed NMR tube.

11

The reaction of a diyne with t-BuMe₂SiH catalyzed by a rhodium(I) complex under an ambient pressure of carbon monoxide reportedly gave a silole via a mechanism involving a Si-Me bond cleavage. See ref. 5f.

12

When 1,6-enyne 8 was employed as the substrate, analogous silylative cyclization occurred to afford bicyclic dihydro-silole 9 in 44% isolated yield (Scheme  [4] ).

Scheme 4