Efficient Pd(0)-Catalyzed Hydrosilylation of Alkynes with Triorganosilanes

Abstract

An electron-rich Pd(0) complex, a Pd₂(dba)₃·CHCl₃-tricyclohexylphosphine combination catalyzes highly efficient hydrosilylation of alkynes at room temperature with Ph₃SiH or Ph₂MeSiH without solvents. The regioselectivity of this process is higher than that with the conventional Pt(0)-catalyzed hydrosilyl­ation.

hydrosilylation - palladium - phosphine - alkyne - alkene

References

<A NAME="RU00402ST-1A">1a</A> Hiyama T. Kusumoto T. In Comprehensive Organic Synthesis   Vol. 8:  Trost BM. Fleming I. Pergamon Press; Oxford: 1991.  Chap. 3.12.

<A NAME="RU00402ST-1B">1b</A> Ojima I. Li Z. Zhu J. In The Chemistry of Organosilicon Compounds, Part 2   Vol. 2:  Rappoport Z. Apeloig Y. Wiley; Chichester: 1998.  Chap. 29.

<A NAME="RU00402ST-1C">1c</A> Corey JY. In Advances in Silicon Chemistry   Larson GL. JAI; Greenwich: 1991.  p.355 

<A NAME="RU00402ST-1D">1d</A> Marciniec B. Comprehensive Handbook on Hydrosilylation   Pergamon Press; Oxford: 1992. 

<A NAME="RU00402ST-2">2</A> Recent examples of hydrosilylation with other catalysts. Ni catalysis: Maciejewski H. Marciniec B. Kownacki I. J. Organomet. Chem.  2000,  597:  175 

Ru catalysis:

<A NAME="RU00402ST-3A">3a</A> Trost BM. Ball ZT. J. Am. Chem. Soc.  2001,  123:  12726 

<A NAME="RU00402ST-3B">3b</A> Na Y. Chang S. Org. Lett.  2000,  2:  1887 

<A NAME="RU00402ST-3C">3c</A> Katayama H. Taniguchi K. Kobayashi M. Sagawa T. Minami T. Ozawa F. J. Organomet. Chem.  2002,  645:  192 

Lewis acid catalysis:

<A NAME="RU00402ST-4A">4a</A> Asao N. Sudo T. Yamamoto Y. J. Org. Chem.  1996,  61:  7654 

<A NAME="RU00402ST-4B">4b</A> Sudo T. Asao N. Gevorgyan V. Yamamoto Y. J. Org. Chem.  1999,  64:  2494 

<A NAME="RU00402ST-4C">4c</A> Yamamoto K. Takemae M. Synlett  1990,  259 

<A NAME="RU00402ST-4D">4d</A> Rubin M. Schwier T. Gevorgyan N. J. Org. Chem.  2002,  67:  1936 

<A NAME="RU00402ST-4E">4e</A> Song YS. Yoo BR. Lee GH. Jung IN. Organometallics  1999,  18:  3109 

<A NAME="RU00402ST-4F">4f</A> Buriak JM. Allen MJ. J. Am. Chem. Soc.  1998,  120:  1339 

Radical Catalysis:

<A NAME="RU00402ST-5A">5a</A> Miura K. Oshima K. Utimoto K. Bull. Chem. Soc. Jpn.  1993,  66:  2356 

<A NAME="RU00402ST-5B">5b</A> Amrein S. Timmermann A. Studer A. Org. Lett.  2001,  3:  2357 

<A NAME="RU00402ST-6A">6a</A> Ojima I. Yatabe M. Fuchikami T. J. Organomet. Chem.  1984,  260:  335 

<A NAME="RU00402ST-6B">6b</A> Hydrosilylation with cationic palladium complexes has been reported, see: Winderhoefer RA. Vadera A. Cheruvu PK. Organometallics  1999,  18:  4614 

<A NAME="RU00402ST-6C">6c</A> Pd-catalyzed hydrosilylation with dimerization of alkynes: Kawanami Y. Yamamoto K. Synlett  1995,  1232 

<A NAME="RU00402ST-6D">6d</A> The Pd₂dba₃·CHCl₃-Cy₃P-catalyzed reaction of alkynes with PhSiH₃ has been reported, see: Yamashita H. Uchimaru Y. Chem. Commun.  1999,  1763 

<A NAME="RU00402ST-7A">7a</A> Jensen JF. Svendsen BY. la Cour TV. Pedersen HL. Johannsen M. J. Am. Chem. Soc.  2002,  124:  4558 

<A NAME="RU00402ST-7B">7b</A> Shimada T. Mukaide K. Shinohara A. Han JW. Hayashi T. J. Am. Chem. Soc.  2002,  124:  1584 

<A NAME="RU00402ST-7C">7c</A> Han JW. Tokunaga N. Hayashi T. J. Am. Chem. Soc.  2001,  123:  12915 

<A NAME="RU00402ST-7D">7d</A> Hayashi T. In Comprehensive Asymmetric Catalysis   Vol. 1:  Jacobsen NE. Pfaltz A. Yamamoto H. Springer; Berlin: 1999.  Chap. 7.

<A NAME="RU00402ST-7E">7e</A> Hayashi T. Acta Chem. Scand.  1996,  50:  259 

<A NAME="RU00402ST-7F">7f</A> Nishiyama H. Itoh K. In Catalytic Asymmetric Synthesis   2nd ed.:  Ojima I. VCH; New York: 2000.  p.111-143  

<A NAME="RU00402ST-8">8</A> For the use of electron rich Pd(0)/trialkylphoshine catalysts, see: Netherton MR. Fu GC. Org. Lett.  2001,  3:  4295 ; and ref. 3 therein

<A NAME="RU00402ST-9A">9a</A> Lewis LN. Sy KG. Bryant GL. Donahue PE. Organometallics  1991,  10:  3750 

<A NAME="RU00402ST-9B">9b</A> Lewis LN. Sy KG. Donahue PE. J. Organomet. Chem.  1992,  427:  165 

<A NAME="RU00402ST-9C">9c</A> Chauhan M. Hauck BJ. Keller LP. Boudjouk P. J. Organomet. Chem.  2002,  645:  1 

<A NAME="RU00402ST-9D">9d</A> For hydrosilylation with Ph₃SiH under other metal catalyses, see: Bartik T. Nagy G. Kvintovics P. Happ B. J. Organomet. Chem.  1993,  453:  29 

<A NAME="RU00402ST-9E">9e</A> Also see: Faller JW. D’Alliessi DP. Organometallics  2002,  21:  1743 

<A NAME="RU00402ST-10">10</A>

Experimental Procedure: The reaction of dodec-1-en-11-yne with Ph₃SiH is representative. In a 30 mL round-bottomed flask, Pd₂(dba)₃·CHCl₃ (5.2 mg, 0.005 mmol) and tricyclohexylphosphine (5.6 mg, 0.02 mmol) were placed under argon atmosphere, and dodec-1-en-11-yne (0.26 mL, 1.2 mmol) was introduced via a syringe. The mixture was stirred well for 10 min to make it homogeneous. To the mixture, triphenylsilane (260 mg, 1.0 mmol) was added at room temperature. Triphenylsilane was soon dissolved and the mixture became homogeneous. After 1 h, the reaction mixture was submitted on silica gel purification to provide (E)-1-triphenylsilyl-dodeca-1,11-diene (369 mg, 0.87 mmol) in 87% yield along with a minor amount of 2-triphenylsilyl-dodeca-1,11-diene (3%).

<A NAME="RU00402ST-11">11</A>

None of alkenylsilanes were obtained with triethylsilane.

<A NAME="RU00402ST-12">12</A> Kinoshita H. Nakamura T. Kakiya H. Shinokubo H. Matsubara S. Oshima K. Org. Lett.  2001,  3:  2521 

<A NAME="RU00402ST-13">13</A>

Experimental Procedure for Aqueous Reaction: In a round-bottomed flask, Pd₂(dba)₃·CHCl₃ (5.2 mg, 0.005 mmol), tris(2,4,6-trimethoxyphenyl)phosphine (10.7 mg, 0.02 mmol), and 1-octyne (0.30 mL, 2.0 mmol) were mixed well. To the mixture, distilled water (5 mL, non-degassed) was introduced and the mixture was stirred vigorously (1500 rpm) for 5 min. Triphenylsilane (260 mg, 1.0 mmol) was then added, and the heterogeneous mixture was stirred vigorously for 6 h. Extractive workup and purification provided (E)-1-triphenylsilyl-1-octene (256 mg, 0.69 mmol) along with 2-triphenylsilyl-1-octene (13%).

<A NAME="RU00402ST-14">14</A>

An addition of a small amount of water (0.1 mL) to the neat reaction did not enhance the reactivity. Therefore, the amount of water is essential.