Lynn Henry Slaugh

Novel Hydroformylation catalysts

Abstract Cobalt carbonyl complexes containing a complementary tertiary phosphine, arsine or phosphite ligand, e.g., [Co(CO)3PBu3]2, have catalytic properties for the hydroformylation of olefins which are considerably different from those of dicobalt octacarbonyl. These novel catalysts are unusual because many are active at low pressures (100–300 psi), produce alcohols rather than aldehydes as the primary product and exhibit a high preference for reaction at the terminal carbon position of I-olefins.

Hydrodimerization of benzene to phenylcyclohexane over supported transition metal catalysts

Abstract Phenylcyclohexane has been obtained in high yield from the hydrogenation of benzene over a variety of supported transition metal catalysts. Both acidity and hydrogenation activity are necessary catalyst properties. Cyclohexene is believed to be a key intermediate which migrates from metal hydrogenation sites to acid sites where subsequent alkylation of benzene occurs.

Dicarbonyl(tributylphosphine)-π-crotylcobalt: structure and reactivity under hydroformylation conditions

Abstract The complex, dicarbonyl(tri-n-butylphosphine)-π-crotylcobalt, (I), recently described by Mertzweiller and Tenney 1 as a hydroformylation catalyst, is unstable under hydroformylation conditions. It is rapidly converted, in the main, to butenes, butane, valeraldehydes, and the previously reported 2,3 active hydroformylation catalyst, bis[(tri-n-butylphosphine)tricarbonylcobalt], (II). Other products include tricarbonyl-π-crotylcobalt, (tributylphosphine)heptacarbonyldicobalt, butadiene, and amyl alcohols. At temperatures and pressures ( e . g ., 110° and 500 psig of synthesis gas) where hydroformylation of 1-heptene occurs to an extent not exceeding 1% over a period of five hours, the complex (II) is always present when hydroformylation is first observed. At higher temperatures, the conversion rate for (I)→(II) is much higher; hydroformylation of 1-heptene proceeds in a similar manner to that which occurs when pure (II) is the initially added complex. It is not possible, therefore, that the complex (I) is the catalytic species responsible for hydroformylation. It is reasonable that the complex (II) promotes hydroformylation in the present instances. Recently, Mertzweiller and Tenney 1 have described a metal complex, dicarbonyl(tributylphosphine)-2-butenylcobalt (I) purportedly capable of lowering the pressures required in the hydroformylation reaction. As part of our continuing study of hydroformylation chemistry 2,3 , we have investigated the detailed structure of this interesting complex and studied its chemistry under hydroformylation conditions.

Addition of acetic acid to bicyclo[2.2.1]Hepta-2,5-diene catalyzed by platinum complexes

Abstract Selected platinum complexes catalyze the stereoselective addition of acetic acid to bicyclo[2.2.1]hepta-2,5-diene to form exo -5-acetoxybicyclo[2.2.1]hept-2-ene. Experiments with acetic acid-O- d 1 have shown that the reaction involves a highly stereoselective skeletal rearrangement of the substrate to produce syn -7-deuterio exo -5-acetoxybicyclo[2.2.1]hept-2-ene. A possible mechanism is presented.

Organic halide-ethylene growth reaction catalyzed by ruthenium complexes

Abstract Ru(CO) 3 (PPh 3 ) 2 and a variety of other zero-valent ruthenium complexes promote the reaction of iodoalkanes with ethylene to produce higher molecular weight 1-iodoalkanes. The chemistry is best explained by the intermediacy of alkyl radicals generated by reaction of the ruthenium complexes with iodoalkanes. With the exception of α-chlorotoluene, organic bromides and chlorides do not undergo the growth reaction.