Reactions of Butene

Two complementai y reviews of this subject are by Shah et al. AIChE Journal, 28, 353-379 [1982]) and Deckwer (in de Lasa, ed.. Chemical Reactor Design andTechnology, Martinus Nijhoff, 1985, pp. 411-461). Useful comments are made by Doraiswamy and Sharma (Heterogeneous Reactions, Wiley, 1984). Charpentier (in Gianetto and Silveston, eds.. Multiphase Chemical Reactors, Hemisphere, 1986, pp. 104—151) emphasizes parameters of trickle bed and stirred tank reactors. Recommendations based on the literature are made for several design parameters namely, bubble diameter and velocity of rise, gas holdup, interfacial area, mass-transfer coefficients k a and /cl but not /cg, axial liquid-phase dispersion coefficient, and heat-transfer coefficient to the wall. The effect of vessel diameter on these parameters is insignificant when D > 0.15 m (0.49 ft), except for the dispersion coefficient. Application of these correlations is to (1) chlorination of toluene in the presence of FeCl,3 catalyst, (2) absorption of SO9 in aqueous potassium carbonate with arsenite catalyst, and (3) reaction of butene with sulfuric acid to butanol. 

Several explanations for this seeming inconsistency can be offered. By far the most attractive is based on unreactivity of certain intermediate ions, and this interpretation is supported by the observation that the reaction of butene ion with ethylene (Reaction 8) appears to occur with a collision efficiency of only about 0.015. The mass spectrometric observation of Reaction 17c (16) indicates that there may be similar low efficiency reactions in sequences initiated by other ions as well. 

In an effort to further support the proposed mechanisms for the Y+propene reaction, we have examined the reactions of Y with four isomeric butenes, which are essentially propene molecules with one additional methyl group (Fig. 31). Based on estimated potential energy barrier heights22 and thermodynamics (Fig. 32))22-31-34,i56,i57 q js eXpected that analogous product channels to those observed for propene should be seen for the butenes. Therefore, a comparison of reactions of butene isomers to reactions with propene should allow us to further test the validity of the proposed mechanisms. Here we briefly summarize our most notable conclusions from this work. 

While preadsorbed oxygen has no effect, the presence of gaseous oxygen drastically changes the product distribution in the thermal desorption and pulse reaction of butene on a-Fe203, as can be seen from results shown in Table VI (6). On this oxide, thermal desorption in an 02 instead of an He carrier results in a much lower yield of hydrocarbons and a much higher yield of C02, The same is observed in pulse reactions. Thus, on a-Fe203, adsorbed butene, adsorbed butadiene, and/or butadiene precursors must be very... 

Thus, the role of the alcohol in the reaction in question is twofold On the one hand, it is the reagent and, on the other, it is a protecting agent that reduces the degree of the undesirable side reaction of butene oligomerization. 

Thus, secondary reactions of butene isomerization and oligomerization proceed over free Al—0(H)—Si sites and yAl—O(R)—Si - sites,... 

The stoichiometric (brutto) equations for the conversion of gas-phase substances are considered. According to them, linear kinetic equations can be obtained, apparently, if only the time scale is changed. These reactions are pseudo-monomolecular and comprehensively treated by Wei and Prater [11]. An example is the familiar reaction of butene isomerization. 

Cvetanovic, R. J., and L. C. Doyle Molecular rearrangement in the mercury-photosensitized reaction of butene-1. J. chem. Physics 37, 543 (1962). 

ANHYD1—reaction of acetone and acetic acid to form acetic anhydride BUTAL1—alkylation reaction of butene-1 and isobutane to produce iso-octane Select the new plant design mode and the look at existing flow sheet option, and follow the synthesis steps for one of these processes. Obtain the current flow sheet as output at each level of the synthesis procedure. Also list the heuristics used at each step. 

Dimethvihexane Formation. Dimethyl hexane formation Is believed to result largely from reactions of butene-l. This includes (I) codimerization of butene-l and isobutene, (2) dimerization of butene-l, and (3) dimerization of isobutene, and (4) isomerization of dimethylhexyl carbonlum Ions each of these reactions is followed by abstraction of a hydride ion from isobutane. Reactions follow ... 

Latremouille and Eastham had already studied a similar esterification process. They found that the reaction of butene-2 with acetic acid-boron fluoride catalytic mixtures in ethylene chloride at 20 °C gave a quantitative yield of the corresponding acetate if the molar ratio [CH3COOH]/[Bp3] was higher than unity. The kinetics of this esterification followed the empirical law ... 

P. B. Venuto (Mobil Oil, Paulsboro, N. J. 08066) Even though your butene reactions occur at low temperatures—relative to thermal free radical reactions—with the presence of polyvalent transition metal ions, radical-type or electron unpairing-type reactions may certainly occur. In your reactions of butene over CeX at 190 °C, did you notice any evidence of an intermolecular hydrogen (hydride) type reaction, as evidenced by light paraffins in the gas phase and hydrogen-deficient species (aromatics) within pores ... 

The isomerization reaction of butene-1 has been carried out with D2SO4 in CH3OD [282). The product contained both deuterated and nondeuterated olefins in a ratio consistent with a random scrambling model. The initial step in the reaction involves an insertion of the olefin into the Ni—H bond to form an alkyl. Elimination from the alkyl obtained by Markownikov addition to the olefin can lead to isomerization, whereas elimination from the anti-Markownikov addition product leads to butene-1 being re-formed. The rate of isomerization to deuteration of the olefin is of the order of 170. 

Since it has been shown that hydrogen migration across the catalyst surface is unlikely, 7 it follows that in this STO procedure each site reacts only once and, thus, there is a 1 1 relationship between the number of specific sites present and the number of molecules of each product formed over these sites. The number of butane molecules produced by the initial reaction of butene with the hydrogen covered catalyst corresponds to the number of direct saturation sites . It has been proposed that these sites give butane by the 3mH2 reaction cycle shown in Scheme 3.4 and, thus, they have been labeled sites. l The formation of butane by reaction of the second pulse of hydrogen with the metalalkyl (Step 3) occurs, presumably, by way of the MH reaction sequence shown in Scheme 3.2. These two-step saturation sites are labeled mH. 

Tsai YL, Koel BE (1997) Temperature programmed desorption investigation of the adsorption and reaction of butene isomers on Pt(lll) and ordered Pt-Sn surface alloys. J Phys Chem B 101 2895... 

Derivation Exchange reaction of butene-1 and isobutyl aluminum. 

Thermal Reactions of Butenes. Among the C4 olefins, 1-butene has been studied most extensively. Bryce and Kebarle (2) pyrolyzed 1-butene at 490° 560°C in a static system, and the main gaseous products were methane, propylene, ethylene, and ethane. The main liquid products were cyclohexadiene, benzene, cyclopentene, cyclopentadiene, and toluene. The rates of formation of methane, propylene, ethylene, and ethane showed first-order dependence on the initial butene concentration. The activation energy for 1-butene disappearance was ca. 66 kcal/mole. 

The effect of additions on catalytic activity is very pronounced in the case of Li20, which strongly inhibits both the reaction of butene and of butadiene. The additions of Li20 also strongly suppress the conductivity of ZnO. Additions of gallia, on the other hand, which have an opposite effect... 

The diene and/or the alkene components can be part of a very complex structure. An example is the reaction of ( )-butenal with 71 to give an 83% yield of 72 in Shirai s synthesis of dysidiolide. Note the regioselectivity and stereoselectivity of the reaction. Note also that it is catalyzed by a Lewis acid which, as mentioned, will be discussed in Section 11.6.A. 

The butene-1 is mixed with butene recycle from the autometathesis recovery section and is vaporized, preheated and fed to the autometathesis reactor (3) where butene-1 reacts with itself to form hexene-3 and ethylene over a fixed bed of proprietary metathesis catalyst. Some propylene and pentene are also formed from the reaction of butene-2 in the butene-1 feed. Reactor effluent is cooled and flows to the autometathesis recovery section (4), where two fractionation columns separate it into a hexene-3 product that flows to the hexene isomerization unit (5), an ethylene/propylene mix, and butene-1 that is recycled to the butene... 

The reaction of butenes over hydroxylated Y zeolites at atmospheric pressure has been investigated using infrared spectroscopy. The results showed a reactivity pattern of the reactants in the order of /ra 5-but-2-ene < cw-but-2-ene < but-l-ene. 

Hexafluoroisobutenylidene sulphate (32) forms compound (33) on heating in a sealed tube at 120—125 °C this may form the perfluoromethacrylic acid derivative (34) at 130 °C, but loses carbon dioxide at 160 °C to form (35), which rearranges to propene (36) on further heating. The sulphate (32) transfers sulphur trioxide to 1,1-difluoro- and tetrafluoro-ethylene on heating, to form the respective sultones.i Reaction of butene (37), from octafluoroisobutene and 2-chloroethanol and triethylamine at —35 to —25 °C, wiUi sulphur trioxide in dichlorodifluoro-... 

NHC-catalysed umpolung of enals appears to be a useful tool for annulation reactions that generally induces molecular complexity from simple starting materials. Enals have thus been reported as appropriate reaction partners for asymmetric annulation reactions with isatins and benzodi(enone)s to yield spirocyclic oxindolo-y-butyrolactones (121), and polycyclic compounds (122), respectively. Both annulation processes have been catalysed by chiral NHCs and accomplished in good yields with high regio- and/or stereo-selectivities. In parallel, the mechanism of the NHC-catalysed annulation reaction of butenal with pentenone has been computationally explored at the B3LYP/6-31+G and M06-2X/6-31G levels of theory. This study has clearly emphasized the key role played by proton-transfer steps in both the rate and the course of the reaction. 

Simple examples of the reactions of olefins with diols are shown in Equations 16.104 and 16.105. Reactions of alkenes typically generate ketals, whereas reactions of olefins bearing electron-withdrawing groups, such as those in acrylates or acrylonitrile, tend to form acetals. This regioseJectivity is shown by the reactions of butene and... 

Petrochemical approaches are the reaction of butene with methallylchloride at 500 °C [5], and the addition of isobutyraldehyde to isobutylene [6] in the presence of a niobium catalyst. 

The yields can be significantly improved with lower olefins using toluene as a solvent and r-butylcatechol as the inhibitor. It is also noteworthy that the reaction of butene-1 and MA gave a 9 1 mixture of isomers.Berson et have also examined cis- and ra/i5-butene-2. Although these workers reported (see Table 5.1) lower yields it was found that the olefins did not interconvert during the reaction. 

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