Inexpensive Facile catalysts are described composed of Nickel Chloride Hexahydrate, Sodium Borohydride, THC, various Fluorinated alcohols to chemoselectively reduce alpha-beta unsaturated systems.
It was found that with a particular Catalyst alpha-beta unsaturated aldehydes and ketones could selectively be reduced adding the Hydrogen, Deuterium, Tritium only to the Carbon-Carbon Double bond; the aldehyde or ketone was left in tact. The triple bond of CN in an alpha beta unstaturated system could also be left untouched with only the double C=C reduced.
A non-toxic fluorinated alcohol (propanol) was used to do the chemoselective reductions listed above (SC-4) as was fluourinated ethanol (SC-3). These reduction reactions gave high yields (quantitative) in just a few minutes in moderate conditions. The catalysts were not air sensitive. The use of SC-3 and SC-4 Catalysts have provided facile means of selective hydrogenation without the need to separate complex organic mixtures since the yields were essentially complete reductions of only the carbon carbon double bond and not the ketone or aldehyde or CN as verified by GC.
Cinnamic acid (C6H5CHCHCOOH) was used as well as other unsaturated systems in the research with these Catalysts. The Benzene ring was also uneffected by the SC-3 and SC-4 catalysts.
Source:
Thurlow, Joseph Richard; Belisle Christopher, Singaram, Bakthan, Williamson, Stanley. University of California, Santa Cruz. Catalytic 1,4-hydrogenation of .alpha.,.beta.-unsaturated
systems using SC-3, SC-4 nickel boride. Thesis 1995.
SC-1, SC-2, SC-3, SC-4 (hydrogenation Catalysts developed and studied in the Singaram Research Labs in the mid 1990s with Stanley Williamson.)
Related Literature
J. C. Fuller, S. M. Williamson, and B. Singaram, "Reduction of alpha,beta-Unsaturated Carbonyl Compounds with Sodium Borohydride in Diethyl Ether/Methanol/Pentafluorophenol Solvent System," J. Fluorine Chem. 68, 205, 1994.
J. C. Fuller, M. L. Karpinski, S. M. Williamson, and B. Singaram, "A fluorine-mediated Boron Reducing Agent: Sodium Tris(pentafluorophenoxy)borohydride. Preparation and Reaction with Selected Organic Compounds Containing Representative Functional Groups. Facile Diastereoselective Reduction of Substituted Cyclohexanones," J. Fluorine Chem. 66, 123, 1994.
J. Golden, C. Schreier, B. Singaram, and S. M. Williamson, "Disproportionation of Alkoxyborohydrides: A 11B NMR Study of the Reaction between Sodium Borohydride and Fluorinated Alcohols and Phenols. The Preparation of Tris(fluoroalkyloxy)- and Tris(fluorophenoxy)borohydrides." Inorg. Chem. 31, 1533, 1992.
Thurlow, Joseph Richard; Belisle Christopher, Singaram, Bakthan, Williamson, Stanley. University of California, Santa Cruz.
Thurlow, Joseph Richard; Belisle Christopher, Singaram, Bakthan, Williamson, Stanley. University of California, Santa Cruz. American Chemical Society. Sonoma State University.
Belisle, Christopher; Thurlow, Joseph R.; Singaram, Bakthan. Catalytic reaction. 1. Catalytic 1,4-hydrogenation of .alpha.,.beta.-unsaturated systems using SC-3 nickel boride.
Belisle, Christopher; Young, Yvette M.; Singaram, Bakthan. Catalytic
reaction. 1. Catalytic 1,4-hydrogenation of .alpha.,.beta.-unsaturated
aldehydes and ketones using SC-1 nickel boride. Tetrahedron Lett. (1994),
35(31), 5595-8.
http://en.wikipedia.org/wiki/Hydrogenation
http://en.wikipedia.org/wiki/Cinnamic_acid
http://en.wikipedia.org/wiki/Catalysis
Nickel boride Catalysts (reduction of nickel salts with sodium or potassium borohydride)P1(in water) and P2(in ethanol 95%) also reduce carbon carbon double bonds selectively. The Letter P with respect to P1 and P2 refers to Purdue University from the Brown Research laboratory where it was developed such as the SC1-SC4 were developed at the University of California, Santa Cruz.)
Modern Organonickel Chemistry, Yoshinao Tamaru, 10.2.2.2, 2005. Wiley.
Other catalysts studied: Lindlar Catalyst, Raney Nickel, (Pt, Pd, Rh catalysts.),
Polymer supported catalysts, Asymmetric catalysis; enantioselective reactions in catalysis, chiral auxiliarie, polymer-supported enzymes...
Hydrogenation catalysis in History:
344 The process to pass the reactant in the vapor phase with hydrogen over the catalytic metal (Pt black, Ni, Co, Fe, Cu) with heat was used by 1902. Nickel was found to be the most active as early as 1902 by Sabatier and other French Chemists.
Catalysis in Organic Chemistry, Paul Sabattier, 1922. 126
Ann. Chim. Phys. (8), 4, 319 (1905).
Sabatier, VIth. Congress Pure and Appl. Chem., Rome, 1906, Xth. Sect. 174.
Sabatier and Mailhe, Ann. Chim. Phys. (8), 16, 70 (1909).
Sabatier Berichte, 44, 1984 (1911).
Sabatier, Address at Stockholm on the reception of the Nobel Prize, Rev. Scient., I, 289 (1913).
Sabatier, Confer. a Toulouse au congres du gaz, Le Gaz, 57, 1914.
Sabatier, Confer. a University of London, Rev. Gle. Chim., 17, 185 and 221 (1914).
Sabatier and Murat Ann de Chim. 9, 4, 253 (1915).
