The +525 °C residues were examined to identify differences between those residue molecules that were converted to smaller distillate molecules and those that were not. Each +525 °C residue was divided into five subfractions by gel permeation chromatography. Molecular weight distributions, elemental (H, C, S, N, Ni, V, and Fe) distributions, and distributions of carbon atom types were determined. With the exception of 10-20%, most of the unconverted +525 °C molecules in the products were similar to the +525 °C feedstock molecules. The ones that were different appeared to have formed by a combination of dehydrogenation and molecular condensation reactions. The macropores in the bimodal catalysts provided diffusion paths for the large molecules to the reaction sites which dissociate hydrogen within the catalyst interior and thereby had a major effect on diminishing these condensation and dehydrogenation reactions. In contrast, the molecules that were converted to distillates were formed by a combination of hydrogenation (greater H/C ratios) and cracking (smaller molecular weights) reactions. An explanation for the same feedstock molecules reacting simultaneously by a dehydrogenation/ condensation sequence and a hydrogenation/cracking sequence is provided by the existence of two liquid phases at reaction conditions, as suggested by Shaw and co-workers. According to this concept, hydrogen is much more soluble in the nonpolar phase (where the hydrogenation/cracking reactions would occur) and much less soluble in the polar phase (where the dehydrogenation/condensaton reactions would occur).

The mass spectra of six furoquinoline alkaloids have been recorded and mechanisms have been proposed for their fragmentation upon electron impact. Strong metastable peaks, present in all spectra, have aided in the interpretation of the fragmentation of these alkaloids. The three alkaloids with a methoxyl group in the 8-position of the quinoline ring may be differentiated from the other three by the presence of relatively intense peaks a t M-1 and M-29.In this investigation we wish to report upon the fragmentation of some furoquinoline alkaloids upon electron impact. The alkaloids which we have examined include dictamnine I and several of its derivatives containing methoxy and methylenedioxy substituents in the benzenoid ring. They are represented in the general formula shown below.The spectra of furan and some of its derivatives have been studied (1, 2) but very little has been reported on the spectra of quinoline and its derivatives (3). No studies t o our knowledge have been reported on the furoquinoline system itself. Oxygenated benzene systems have, however, been investigated in detail (2, 4, 5) and since all of these alkaloids with the exception of dictamnine carry oxygenated substituents in the benzene ring one might expect t o observe fragmentation processes akin to those of the oxygenated benzenes.T h e spectra of the six alkaloids are shown in Fig. 1. All show a n intense molecular ion peak a s one would expect of this aromatic system. I n each case they also exhibit a peak a t M-15 owing to the loss of a methyl group characteristic of the presence of methoxyl substituents. Of structural interest is the fact t h a t the three alkaloids with a n 8-methoxyl substituent show strong peaks a t M-1 and M-29. This behavior is also characteristic of 8-methoxy quinolines which we have measured in this laboratory. I t seems very likely, therefore, t h a t an 8-methoxyl substituent will give this characteristic pattern in all furoquinoline alkaloids.I n attempting t o rationalize the fragmentation of these alkaloids we have first examined the spectrum of dictamnine, the simplest member of the group, and have then examined the spectra of the other alkaloids t o ascertain if they undergo similar fragmentation processes.

At 95-115", paraformaldehyde and hydriodic acid completely C-methylate aromatics such as benzene and phenol. Pyrroles are C-methylated similarly, carbethoxy and acetyl groups being lost. In hydriodic acid at 1545", typical pyrroles retain these groups and all free positions are C-alkylated, methylated by paraformaldehyde, or otherwise alkylated by the appropriate carbonyl compound. The alkylation of a 2-free-by a 2-formylpyrrole led to a dipyrrylmethane. With pyrroles, hydriodic acid may be replaced by another strong acid and a reducing agent. This was necessary when a 0-free pyrrole gave the iodo-alkyl derivative rather than the expected product.

The mass spectra of the n~o~lohydroxyquinoli~ies, the n~onomethoxyquinolines, N-methyl-2-quinolone, and N-methyl-4-quinolone have been recorded. The isomeric hydroxy compounds vary somewhat in the stability of the molecular ion, but all show the same fragmentation mechanism. Two general fragmentation patterns are discernible in the spectrum of each of the mono~nethoxyq~~inolines, but there is considerable variation among the isomers in the extent to which the two patterns occur. In addition, 8-methoxyquinoli~~e undergoes a peculiar fragmentation wherein all three methyl hydrogens are lost. The 3-methoxy con~pound is unusual in that loss of 43 Inass units from the molecular ion occurs in one step. Deuterium-and '"C-labelling experiments have proved to be useful in interpreting the fragmentation pathways.The spectra of the two N-methylquinolones prove that 0 to N methyl rearrangement does not occur to any significant extent upon electron impact.In a recent paper we reported on the behavior of some furoquinoline alkaloids upon electron impact (I). Except for quinoline (2) and some alkylquinolines (2, 3), no other systematic study of fragmentation in a quinoline system has been reported. I t seemed appropriate, therefore, to examine the mass spectra of some simple oxygenated quinolines without the complicating effect of the furan ring present in the furoquinoline alltaloids. In this investigation, therefore, we report on the fragmentation of the seven n~onomethoxy-quinolines, the seven monohydroxyquinolines, and the two isomeric N-methylquinolones.Although the spectra of substituted quinolines have not been discussed, the spectra of other substituted aromatic systems have been examined in detail. The spectra of some methoxy derivatives of benzene (2, p. 174ff; 4) and naphthalene ( 5 ) have been reported, as have the spectra of phenols (6). I n these compounds as well as in aromatic systems containing other substituents (2, p. 186ff; 4 ; 7), marked differences in the fragmentation of isomers have been noted. The mass spectra of several nitrogen-containing heterocyclic aromatic systems have been examined, and in many of them the loss of hydrogen cyanide has been found to be a major fragmentation pathway (2, p. 251ff). I n 2-and 4-pyridone the spectra exhibit intense pealts for the loss of carbon monoxide (8). One might expect, therefore, that the quinoline derivatives discussed below would undergo fragmentation by pathways similar to those cited above. Our results show that this is so and that the expected differences among the various isoillers are found.The spectra of the monomethoxyq~~inolines are recorded in Fig. 1. I t will be noted that there is considerable variation among the isomers, but that they can be divided into two main groups. The first group is made up of the 2-and 8-isomers while the second group comprises the rest. The major pealts found in each spectrum can be accounted for by two fragmentation schemes, both of which involve the methoxyl group in the initial fragmentation. Scheine 1 depicts...

The hydrocarbon-type content of petroleum fractions has tradltlonally been determlned by uslng different techniques but often wlth poor agretsment among the varlous results for a glven sample. In thls study, three different fractlons were analyzed by using mass spectrometric (MS), nuclear magnetlc resonance (NMR), and fluorescent Indicator analysis (FIA) techniques. The lac and 'H NMR results were flrst converted from an atomic to a molecular bask. The MS, NMR, FIA, and bromllne number results are compared, wlth special attention given to the olefinlc contents. The assumptlons Involved In, and lirnltations of, each technlque are Identified. The analysis of llght fractions free of dlenes, olefins, and heteroatom-ccontalning species is best performed by MS methods. The atomic hydrogen and carbon dlstrlbutlon from the NMR method Is found to be applicable to all samples examined. Whlle these atomic data can be correlated with the properties of the fractlons, the NMR resuns on a molecular basis are uncertain because of the number of assumptions Involved.Performance characteristics and other properties of petroleum products depend on their chemical compositions. Among the determining factors is the content of aromatic, olefinic, and saturated hydrocarbons. For example, the amounts of aromatic and saturated hydrocarbon affect the combustion properties of fuels, while olefins have a marked effect on a fuel's stability.Petroleum fractions must be subjected to various refining treatments to meet final product specifications. Such treatments always lead to a change in the constituent hydrocarbons. A rapid method of determining the proportions of the hydrocarbons would be a valuable tool for controlling technological parameters during production.Mass spectrometric (MS) techniques have been extensively applied, for many years to various types of hydrocarbon analysis, and new developments have been periodically reviewed (1). A number of MS analytical methods were standardized (2). ThLese can be applied with good precision to samples which fall within the limitations of the methods. Two important limitations are that there be very low amounts of olefins and of heteroatom (i.e., S-, N-, 0-) containing compounds. Both these classes of compounds are a source of interference in the calculations based on the spectral information. It appears,, therefore, that MS methods are suitable only for analyzing refined products from which these interferences are usually absent.Nuclear magnetic resonance spectrometry (NMR) is a powerful tool in fuel analysis as well (3). Preferential use of this technique in analysis of coal-derived liquids, i.e., liquids with high content of heteroatoms, suggests that the interference of the latter i8 less critical. An additional advantage of NMR over MS is NMR's ability to analyze nonvolatile samples, including semisolids and solids.The gas chromatographic-mass spectrometric (GC/MS) technique acts at a molecular level; that is, there is a molecular separation followed by detection and analysis of molecules. T...