Grubbs Hydrocarbon

FIG. 19-13 Noncatalytic gas-phase reactions, (a) Steam cracking of light hydrocarbons in a tubular fired heater, (b) Pebble heater for the fixation of nitrogen from air. (c) Flame reactor for the production of acetylene from hydrocarbon gases or naphthas. [Patton, Grubb, and Stephenson, Pet. Ref. 37(11) 180 (1958).] d Flame reactor for acetylene from light hydrocarbons (BASF), (e) Temperature profiles in a flame reactor for acetylene (Ullmann Encyclopadie der Technischen Chemie, vol. 3, Verlag Chemie, 1973, p. 335). 

Synthetic methods targeting amino acid incorporation into functional materials vary widely. Free-radical polymerization of various amino acid substituted acrylates has produced many hydrocarbon-amino acid materials [161, 162]. In separate efforts, MorceUet and Endo have synthesized and meticulously characterized a library of polymers using this chain addition chemistry [163- 166]. Grubbs has shown ROMP to be successful in this motif, polymerizing amino add substituted norbornenes [167-168]. To remain within the scope of this review, the next section wiU focus only on ADMET polymerization as a method of amino add and peptide incorporation into polyethylene-based polymers. 

Grubb WT (1963) Catalysis, electrocatalysis, and hydrocarbon fuel ceUs. Nature 198 883... 

Side-chain crosslinked helices obtained from an olefin metathesis reaction were first described by Blackwell and Grubbs [110], and more recently by Schafmeister and Verdine [70]. These researchers carefully examined linker length and stereochemistry to arrive at the optimal design. The hydrocarbon-stapled helices were subsequently shown to target antiapoptotic proteins HDM2 and Bcl-2 BH3 domain proteins in cell culture and animal models [37, 111]. The hydrocarbon linker was employed because it was expected to be chemically more stable than linkers built from amide or disulfide bonds but, significantly, these hydrocarbon-stapled helices have also shown an increased tendency to penetrate cell membranes, possibly due to the lipophilic nature of the linker. Debnath and... 

All these studies as well as the work of Leonard Niedrach and Thomas Grubb, mentioned earlier, concerning the possibility of low-temperature hydrocarbon oxidation, led to the development of a new branch of electrochemical science, electrocatalysis. ... 

Figure 11 Reaction of a peptide containing two olefin substituents with the second generation Grubb s catalyst forms a hydrocarbon bridge that serves as a hydrogen bond surrogate.

A series of methyl-substituted polymers, with varying numbers of methylene units between the terminal olefin and the branch point [58], demonstrated that, when there are at least two methylene units separating the olefin and branch point, there is little effect on the catalysis of the reaction. A series of poly(l,4-alkylenephenylene)s have also been prepared by ADMET with Schrock s molybdenum, Grubbs first-generation, and classical catalysts [59]. This series demonstrated that hydrocarbon dienes containing aromatic groups are readily polymerizable by ADMET, even when there is only one methylene unit between the olefin and the aromatic group. 

Figure 2.6 GE s Thomas Grubb (left) and Leonard Niedrach run a fan with a hydrocarbon-fed PEMFC, April 1963. (From Smithsonian Institution, neg. EMP059029, from the Science Service Historical Images Collection, courtesy of General Electric.)...

It was the aim of this work to find ways to raise the rate and efficiency of the electrochemical reactions taking place at the electrodes of fuel cells, mainly by raising their catalytic activity. These studies examined reactions at both the oxygen (air) electrode and at the hydrogen electrode (see the monograph of M. Breiter, 1969). In many countries, the special features of electrochemical oxidation of methanol at platinum catalysts were also studied. All these studies, as well as the work of Grubb and Niedrach mentioned earlier, concerning the possibility of low-temperature hydrocarbon oxidation led to the development of a new branch of electrochemical science, electrocatalysis. 

In parallel with the high-temperature work, attempts continued to achieve low-temperature oxidation of methane and other hydrocarbons in aqueous solutions, a possibility first pointed out by Grubb and Niedrach in 1963. Alkaline electrolytes cannot be used with such carbon-based fuels the carbon dioxide that is a reaction product, together with water, would transform the alkaline solution to carbonate solutions not suitable as an aqueous fuel cell electrolyte. 

Some general reviews relating to the chemistry of Ru/Os-r hydrocarbon complexes appear in the literature the reactivity of Ru-H bonds with alkenes and alkynes/ aspects of ruthenium/osmium vinylidene/allenylidene/cumul-enylidene complexes,equilibria of M-R/M=CR2/M=CR complexes, the organometallic chemistry of metal porphyrin complexes, and the reactions of [Os(P Pr3)2(CO)HGl], ruthenium pyrazoly I borate complexes,and metallabenzynes. Other reviews relate more to applications of some of the complexes outlined in this chapter. See, for example, metal vinylidenes in catalysis,the development of Grubbs-type alkene metathesis catalysts, applications of ruthenium/osmium carbene complexes in metathesis polymerization, and the role of Ru /V-hetero-cyclic carbene complexes in metathesis polymerization. ... 

Simple nonfunctional hydrocarbon polymers such as polyethylene (PE), polypropylene, poly-a-olefins and their copolymers are synthesized by uncontrolled high-pressure-high-temperature radical, metathesis or transition-metal-catalyzed coordination polymerization (Natta, 1956 Ziegler et al, 1955 Wu and Grubbs, 1994 Chanda and Roy, 1993). Although catalysts of exceptional efficiency that produce polymers on a huge scale are in common use, control that approaches a hving polymerization for these methods has not been realized. 

Books have been published on cyclic polyolefin complexes and metal vapour synthesis, while a review on metal vapour cryochemistry also contains information relevant to the latter. Reviews have also been published on organometallic derivatives of alkenes and ketenes, cationic Rh diolefin complexes, and nucleophilic addition to cationic hydrocarbon complexes. More personalized reviews have appeared by Maitlis on Pd -acetylene chemistry, by Jonas and Kruger on alkali-metal-transition-metal w-complexes, and by Werner on bridged allyl and cyclopentadienyl complexes. Articles by Wilke on homogeneous catalysis, by Vollhardt on metal-mediated approaches to steroid synthesis, by Schrock > on organotantalum chemistry, and by Grubbs on nickel metallocycles also contain material of relevance to r-complexes. 

Grubbs, R.H. and Kratz, D. (1993) Highly unsaturated oligomeric hydrocarbons-a-(phenylethynyl)-co-phenylpoly[l,2-phenylene (2,1-ethynediyl)]. Chemische Berichte, 126(1), 149-157. 

Binder and others [230] found that Raney platinum was the best single catalyst for electrochemical oxidation of hydrocarbons. Data obtained by Bianchi [231], Grubb [232], and Cairns and Mclnemey [203], who compared the catalytic activities of various platinum blacks in the anodic oxidation of propane, are consistent with this conclusion. As found by Petrii and Marvet [100], the oxidation rate of methane decreases sharply on changing from platinum to other platinum catalysts. Bockris and Dahms [192] showed that the oxidation rate of ethylene decreases in the series Pt > Rh > Ir and Pd > Au, where platinum is considerably more active than palladium. It was found in [233] that the oxidation rate of propane in alkali decreases in the order Pd > Pt > Ag, and those of ethane ethylene, propylene, and n-butane decrease in the order Pt > Pd... 

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