Hydrogen dimer

Phosphorus ylids react with carbon dioxide to give the isolable salts (48), which can be hydrolyzed to the carboxylic acids (49) (thus achieving the conversion RR CHX RR CHCOOH) or (if neither R nor R is hydrogen) dimerized to... 

The hydrogenated dimer of 1-decene [1208] can be used instead of conventional organic-based fluids, as can n-l-octene [1105]. 

Thus, the bond order is one-half the difference between the number of electrons in the bonding state compared to the antibonding state. It takes its maximum value of unity when the bonding state is totally occupied with two electrons of opposite spin and the antibonding state has no electrons as, for example, in the hydrogen dimer. 

Sulfuric acid polymerization plants found their greatest application in the aviation gasoline program. Cold acid plants were generally converted to the hot acid type because the yield of the latter is much higher with only a very small sacrifice in octane value of the hydrogenated dimer. 

Reid vapor pressure. 6 C -f gasoline. e Hydrogenated dimer. 

Fig. 6.5. Computed structures due to the hydrogen dimer, in the quadrupole-induced (0223,2023) components near the So(0) line center at 120 K (the temperature of Jupiter s upper atmosphere). Superimposed with the smooth free — free continuum (dashes) are structures arising from bound — free (below 354 cm-1) and free - bound (above 354 cm-1) transitions of the hydrogen pair (dotted). The convolution of the spectrum with a 4.3 cm-1 slit function (approximating the instrumental profile of the Voyager infrared spectrometer) is also shown (heavy line) [282].

The most striking hydrogen dimer features are, however, not due to bound-bound transitions, but to bound-free and free-bound transitions, just as this was concluded above, pp. 316ff. Figure 6.19 shows a comparison... 

L. Frommhold, R. Samuelson, and G. Birnbaum. Hydrogen dimer structures in the far-infrared spectra of Jupiter and Saturn. Astrophys. J., 283 L79, 1984. 

A. R. W. McKellar. Experimental verification of hydrogen dimers in the atmospheres of Jupiter and Saturn from Voyager IRIS far-infrared spectra. Astrophys. J., 326 L75, 1988. 

Rosin. Rosin is used mainly in some modified form. Because the abietic-type acids in rosin each contain a carboxyl group and double bonds, they are reactive and can be used to produce salts, soaps, esters, amines, amides, nitriles, and Diels Alder adducts and they can be isomerized, disproportionated, hydrogenated, dimerized, and polymerized. When destructively distilled, rosin produces a viscous liquid, termed rosin oil, used in lubricating greases. 

These phosphines are typically used as ligands for catalytic reactions such as hydroformylation, hydrogenation, dimerization, and other metal-catalyzed reactions. Other uses for the phosphorus derivatives are Wittig chemistry (vitamin A and E), phase-transfer catalysis, epoxy curing, extractants, and agricultural and pharmaceutical intermediates. 

Treatment of (PhCH2)4Ti with Hj in the presence of MejPCHjCHjPMej (L) gives LjTiHj, which catalyses the hydrogenation, dimerization, and polymerization of olefins. ... 

Heck, R. F., Accounts Chem. Res., 1969, 2, 10 (general review on addition reactions hydrogenation, dimerization, carbonylation, etc.). 

Some researchers have suggested that one-electron transfer from the amide irai to an aromatic substrate plays the key role in this reaction [9,10,40]. Dimerization of the starting aromatic compounds or the formation of partially hydrogenated dimers, which are sometimes observed in the course of the Chichibabin reaction, can be considered as indirect arguments in favor of this hypothesis. 

Fig. 19. Catalytic hydrogenative dimerization of tBuC=CH by [IrH2(P Pr3)(NCMe)3] species.

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