Ruthenium-Catalyzed Addition Reaction of Alcohols across Olefins

Abstract

2-Phenylethanol was added to olefins catalyzed by ruthenium catalytic system Cp^*RuCl₂(PPh₃)/2AgOTf in toluene. This ­reaction proceeded without β-hydride elimination, giving saturated ethers in good yields.

Key words

addition reactions - ruthenium - alcohols - alkenes - ethers

References

• 1 For review, see: Burgess K. Ohlmeyer MJ. Chem. Rev.  1991,  91:  1179 
• 2 For example: Glaser PB. Tilley TD. J. Am. Chem. Soc.  2003,  125:  13640 
• 3a Kawatsura M. Hartwig JF. J. Am. Chem. Soc.  2000,  122:  9546 
• 3b Utsunomiya M. Hartwig JF. J. Am. Chem. Soc.  2003,  125:  14286 
• 3c Utsunomiya M. Hartwig JF. J. Am. Chem. Soc.  2004,  126:  2702 
• 4 Shellhamer DF. Callahan RP. Heasley VL. Druelinger ML. Chapman RD. Synthesis  1997,  1056 
• 5 Brown HC. Kurek JK. Rei M.-H. Thompson KL. J. Org. Chem.  1984,  49:  2551 
• 6 Kondo T. Tsunawaki F. Sato R. Ura Y. Wada K. Mitsudo T. Chem. Lett.  2003,  32:  24 
• 7a Hori K. Kitagawa H. Miyoshi A. Ohta T. Furukawa I. Chem. Lett.  1998,  1083 ; and unpublished data
• 7b Recently, Widenhoefer et al. achieved platinum-catalyzed intramolecular hydroalkoxylation of hydroxy olefins. See: Qian H. Han X. Widenhoefer RA. J. Am. Chem. Soc.  2004,  126:  9536 
• 8 Oe Y. Ohta T. Ito Y. Chem. Commun.  2004,  1162 
• 9 Oshima N. Suzuki H. Morooka Y. Chem. Lett.  1984,  1161 

10

Typical Procedure of Ruthenium-Catalyzed Hydroalkoxylation Reaction of 2-Phenylethanol(1) with Styrene ( 2a) Described in Table 2, Entry 1.
Cp^*RuCl_{2 (}Ph₃P) (11 mg, 0.02 mmol) was dissolved in toluene (2 mL) and the solution was heated to 85 °C. After 15 min, AgOTf (11.5 mg, 0.045 mmol) was added and stirred at 85 °C for 3 h. The reaction mixture was cooled to r.t. 2-Phenylethanol (1, 122 mg, 1.0 mmol) and styrene (2a, 260 mg, 2.5 mmol) were added. The reaction mixture was heated to 70 °C and stirred for 48 h. The crude product was purified by silica gel chromatography (hexane-EtOAc = 10:1), yielding product 3a (187 mg, 83%).