Subscribe to RSS
DOI: 10.1055/s-2006-951518
RuHCl(CO)(PPh3)3-Catalyzed Reductive Dimerization of α,β-Unsaturated Aldehydes Leading to α-Hydroxymethyl Ketones
Publication History
Publication Date:
25 October 2006 (online)
Abstract
The reductive dimerization α,β-unsaturated aldehydes to give saturated ketones was achieved using RuHCl(CO)(PPh3)3 as a catalyst in the presence of secondary alcohols as hydrogen source. The reaction is likely to proceed via the hydroruthenation of α,β-unsaturated aldehydes followed by aldol reaction of the resultant ruthenium enolates with α,β-unsaturated aldehydes to give unsaturated α-hydroxymethyl ketones, which undergo transfer hydrogenation to give α-hydroxymethyl ketones.
Key words
ruthenium enolates - aldol reaction - α-hydroxymethyl ketones - α,β-unsaturated aldehydes - transfer hydrogenation
-
1a
Transition Metals for Organic Synthesis
Vols. 1 and 2:
Beller M.Bolm C. Wiley-VCH; Weinheim: 1998. -
1b
Applied Homogeneous Catalysis with Organometallic Compounds
Vols. 1 and 2:
Cornils B.Herrmann WA. VCH; Weinheim: 1996. - 2
Doi T.Fukuyama T.Minamino S.Husson G.Ryu I. Chem. Commun. 2006, 1875 - 3
Doi T.Fukuyama T.Horiguchi J.Okamura T.Ryu I. Synlett 2006, 721 - For studies on ruthenium enolate complexes, see:
-
5a
Hartwig JF.Bergman RG.Andersen RA. Organometallics 1991, 10: 3326 -
5b
Tasley BT.Rapta M.Kulawiec RJ. Organometallics 1996, 15: 2852 - For Ru-catalyzed aldol-type reactions, see:
-
6a
Matsuda I.Shibata M.Sato S. J. Organomet. Chem. 1988, 340: C5 -
6b
Sato S.Matsuda I.Shibata M. J. Organomet. Chem. 1989, 377: 347 -
6c
Naota T.Taki T.Mizuno M.Murahashi S.-I. J. Am. Chem. Soc. 1989, 111: 5954 -
6d
Mizuho Y.Kasuga N.Komiya S. Chem. Lett. 1991, 2127 -
6e
Murahashi S.-I.Naota T.Taki H.Mizuno M.Takaya H.Komiya S.Mizuho Y.Oyasato N.Hiraoka M.Hirano M.Fukuoka A. J. Am. Chem. Soc. 1995, 117: 12436 -
6f
Uma R.Davies M.Crévisy C.Grée R. Tetrahedron Lett. 2001, 42: 3069 -
6g
Wang M.Yang X.-F.Li C.-J. Eur. J. Org. Chem. 2003, 998 -
6h
Yang X.-F.Wang M.Varma RS.Li C.-J. Org. Lett. 2003, 5: 657 -
6i
Yang X.-F.Wang M.Varma RS.Li C.-J. J. Mol. Catal. A: Chem. 2004, 214: 147 -
6j
Martín-Matute B.Bogár K.Edin M.Kaynak FB.Bäckvall J.-E. Chem. Eur. J. 2005, 11: 5832 - For reviews on catalytic reductive aldol coupling, see:
-
7a
Motherwell WB. Pure Appl. Chem. 2002, 74: 135 -
7b
Huddleston RR.Krische MJ. Synlett 2003, 12 -
7c
Jang H.-Y.Krische MJ. Eur. J. Org. Chem. 2004, 3953 -
7d
Jang H.-Y.Krische MJ. Acc. Chem. Res. 2004, 37: 653 -
7e
Chiu P. Synthesis 2004, 2210
References and Notes
After 15 min, 3a contained ca. 17% of double-bond isomers.
8General Procedure for the RuHCl(CO)(PPh 3 ) 3 -Catalyzed Reductive Dimerization of α,β-Unsaturated Aldehyde. A mixture of 1a (103 mg, 1.03 mmol), 2-PrOH (63 mg, 1.05 mmol), and RuHCl(CO)(PPh3)3 (96.0 mg, 0.1 mmol) in benzene (6 mL) was stirred at reflux for 10 h under an atmosphere of N2. Purification by silica gel column chromatography and preparative HPLC equipped with GCP column gave α-hydroxymethyl ketone 2a (59.0 mg, 59%).