Butenes 3-methylpentanal

Alkenes with a 1,1-disubstitution pattern form tertiary carbocations upon treatment with a Brpnsted acid. Consequently, such compounds are often easily reduced (Eq. 72). An example of this is the formation of 2-methylpentane in 93% yield after only 5 minutes when a dichloromethane solution of 2-methyl-1-pentene and 1.4 equivalents of triethylsilane is treated with 1.4 equivalents of trifluoromethanesulfonic acid at —75°.216 Similar treatment of 2,3-dimethyl-l-butene gives a 96% yield of 2,3-dimethylbutane.216... 

Methylpentane propene > ethene > butene > methane a pentene > ethane... 

Rhodium-phosphine catalysts are unable to hydroformylate internal olefins, so much that in a mixture of butenes only the terminal isomer is transformed into valeraldehydes (see 4.1.1.2). This is a field still for using cobalt-based catalysts. Indeed, [Co2(CO)6(TPPTS)2] -i-lO TPPTS catalyzed the hydroformylation of 2-pentenes in a two-phase reaction with good yields (up to 70%, but typically between 10 and 20 %). The major products were 1-hexanal and 2-methylpentanal, and n/i selectivity up to 75/25 was observed (Scheme 4.12). The catalyst was recycled in four mns with an increase in activity (from 13 to 19 %), while the selectivity remained constant (n/i = 64/36). 

The hydroformylation of several olefins in the presence of Co2(CO)8 under high carbon monoxide pressure is reported. (S)-5-Methylheptanal (75%) and (S)-3-ethylhexanal (4.8%) were products from (- -)(S)-4-methyl-2-hexene with optical yields of 94 and 72%, respectively. The main products from ( -)(8)-2,2,5-trimethyl-3-heptene were (S)-3-ethyl-6,6-di-methylheptanal (56.6%) and (R)-4,7,7-trimethyloctanal (41.2%) obtained with optical yields of 74 and 62%, respectively. (R)(S)-3-Ethyl-6,6-dimethylheptanal (3.5% ) and (R)(S)-4,7,7-trimethyloctanal (93.5%) were formed from (R)(S)-3,6,6-trimethyl-l-heptene. (+/S)-l-Phenyl-3-methyl-1-pentene, under oxo conditions, was almost completely hydrogenated to (- -)(S)-l-phenyl-3-methylpentane with 100% optical yield. 3-(Methyl-d3)-l-butene-4-d3 gave 4-(methyl-d3)pentarwl-5-d3 (92%), 2-methyl-3-(methyl-d3)-butanal-4-d3 (3.7%), 3-(methyl-d3)pentanal-2-d2,3-d1 (4.3%) with practically 100% retention of deuterium. The reaction mechanism is discussed on the basis of these results. 

The addition of HBr to 2-methyl-l,3-pentadiene, 1-bromo-1,3-butadiene, 1-phenyl-1,3-butadiene and 2,4-hexadiene produces 2,4-dibromo-2-methylpentane, 1,3-dibromo-l-butene, 3-bromo-l-phenyl-1-... 

The first asymmetric hydroformylation with platinum catalysts was carried out42 using NMDPP as the asymmetric ligand. An optical yield of 9% was obtained in the hydroformylation of 2-methyl-l-butene to 3-methylpentanal. Subsequently, different types of olefins were asymmetrically hydroformylated using a catalytic system formed from [(—)-DIOP]PtCl2 and SnCl2 2 H20 in situ 42,45) (Table 4). 

Bromo-3-methylpentane 3-Methyl-2-pentene 2-Ethyl-l-butene... 

Methylpentanal. Early studies of propanal and 1-butanal in the gas phase have been reviewed by Cundall and Davies (61). Only a few other saturated aldehydes have been studied recently, and 3-methylpentanal is one of them. Rebbert and Ausloos (195) have compared the direct and the triplet-sensitized photolysis of 3-methylpentanal, since this molecule can undergo two kinds of intramolecular rearrangement process / Norrish type II process 18, a primary or a secondary a-hydrogen atom transfer to the carbonyl oxygen, giving 1-butene or trans/cis-2-butene, respectively. 

Before discussing the "trityl" ion it is important to note that the methylpentane isomerization is slow in fresh acid (there s an induction period as with 2,3,4-trimethylpentane), but may be accelerated by the addition of small amounts of an olefin like 2-methyl-l-butene. However, the reaction initiated by the olefin is rapidly quenched as the acid reduces a momentarily high intermediate ion concentration to a steady state level. The reduced rate is now a measure of the hydride transfer rate in the acid. The data to be discussed were obtained at 23°C with emulsions containing equal volumes of methylpentane and 95 percent H2S0. ... 

Slobodin et al. [39] confirmed that thermal decomposition of EPR (equimolar ratio) began at 170 °C and ceased at 360 C. A total 93.66% condensate products, 5.2% gas and 1.14% carbonaceous residue were obtained, mainly at 235 °C. The composition of the gaseous portion, determined by GLC was ethane-ethylene 1.25%, propane 0.81%, propylene 0.98%, butane-butylene 0.99% and butadiene 0.99% by wt. of EPR. The liquid products were separated into five fractions with boiling ranges of 100 C, 100-150 C, 150-200 °C, 200-250 °C, and >250 °C. The fractionation yielded pentane, 1-pentene, 2-methylbutane, 2-methyl-l-butene, 2-methyl-2-butene, isoprene and piperylene of C5 hydrocarbon and hexane, 1-hexane, 2-methylpentane of Cg hydrocarbons. Based on these data, the thermal degradation was proposed to proceed via a free-radical mechanism. A free radical CH3... 

The radiolysis of propane has been studied extensively in experiments that have included a wide range of techniques. The gas-phase radiolysis in the absence of inhibitors yields the products hydrogen, ethane, propene, 2,3-dimethylbutane, methane, ethylene, isobutane, acetylene, isopentane and n-butane as well as small quantities of butene-1, -pentane, 2-methylpentane and -hexane ° ° . At high conversions the yield of ethylene, propene, 2,3-dimethylbutane and isobutane are all reduced. The reduction in ethylene arises from hydrogen atom addition, while the reduction in the other products may arise from the reaction of propyl ions with propene to remove both C3H6 and the source of isopropyl radicals. 

The results of pyrolysis of polypropylene in air depends on the pyrolysis heating rate because the pyrolysis process competes with the oxidation [108], By heating between 120° C and 280° C in air, polypropylene is reported to generate ethene, ethane, propene, propane, isobutene, butane, isobutane, pentadiene, 2-methyl-1-pentene, 2,4-dimethyl-1-pentene, 5-methyl-1-heptene, dimethylbenzene, methanol, ethanol, 2-methyl-2-propene-1-ol, 2-methylfuran, 2,5-dimethylfuran, formaldehyde, acetaldehyde, acrolein, propanal, methacrolein, 2-methylpropanal, butanal, 2-vinylcrotonaldehyde, 3-methylpentanal, 3-methylhexanal, octanal, nonanal, decanal, ethenone, acetone, 3-buten-2-one, 2-butanone, 1-hydroxy-2-propanone, 1-cyclopropylethanone, 3-methyl-2-buten-2-one, 3-penten-2-one, 2-pentanone, 2,3-butanedione [109]. 

There are three possible types of shape and size selectivity effects, as shown in Fig. 4.2S. First, the reactant molecules may be too large to enter the cavities. Comparison of Tables 4.11 and 4.13 shows that all of the molecules access faujasite structures. Only molecules larger than penta-methyl benzene are excluded. Early examples of shape and size selectivity were almost completely limited to small openings and normal versus branched paraffins. For example, n hexane was selectively cracked in the presence of 3-methylpentane over zeolite A catalysts. Other, more subtle, effects may occur. The diffusivity of frart5 butane-2 is 200 times larger than that of cis-butene-2 in zeolite CaA. By adding Pt to CaA, selective hydroge nation of fr[Pg.79]

All the measured traffic profiles were found to be very similar. The same distribution could be observed for tunnel, intersection and street and freeway driving measurements. The highest contribution was from toluene, about 20%, with major contributions also from enzene, 7 a-xylene, 2-methylpentane, isopentene, 1-butene and isobutene,... 

The best induction is achieved with isoprene leading to 3-methylpentanal (7) (> 30% ee)18-64. Interestingly, these results arc better than those with 2-methyl-l-butene using the same catalyst. This indicates different mechanisms for the conversion of the monoalkene and its corresponding diene18. 

Hamill, Guarino, and Ronayne (II) gamma irradiated 0.18 mole % benzyl chloride in glassy 2-methyltetrahydrofuran (MTHF) at liquid nitrogen temperature and obtained a maximum ultraviolet absorption band at 320 m/x in agreement with Porter and Strachan, see Table I. They also irradiated 1.0 mole % allyl chloride, allyl bromide and allyl alcohol in 3-methylpentane (3-MP) and in all cases observed a maximum absorption band at 228 m/x which they attributed to the allyl free radical. They also irradiated 3-chloro-1-butene and 3-chlorocyclohexene in 3-MP and determined the wavelengths of the absorption band maxima of the 1-methyl allyl and 2-cyclohexen-l-yl free radicals given in Table I. 

Fig. 5-2. Plot of relative disappearance rates for hydrocarbons observed in smog chambers versus OH rate coefficients (in units of cm3/molecules s) from independent measurements. Key (1) n-butane, (2) isobutane, (3) n-pentane, (4) isopentane, (5) n-hexane, (6) 2-methylpen-tane, (7) 3-methylpentane, (8) cyclohexane, (9) ethane, (10) propene, (11) 1-butene, (12) isobutene, (13) ds-2-butene, (14) frans-2-butene, (15) 1-pentene, (16) methyl-l-butene, (17) cis-2-pentene, (18) 1-hexene, (19) 3,3-dimethylbutene, (20) cyclohexene, (21) toluene, (22) o-xylene, (23) m-xylene, (24) p-xylene, (25) 1,2,3-trimethylbenzene, (26) 1,2,4-trimethylben-zene, (27) 1,3,5-trimethylbenzene. Open circles from Wu el al. (1976) relative to c/s-2-butene, upper scale hatched circles from Lloyd etal. (1976) and Pitts eial. (1978) relative to n-butane, lower scale.

Fig. 5.1. Chromatograms of products of catalytic cracking (A) without reactor and (B) with reactor. Sorbent, 11% quinoline on refractory brick temperature, 25 C column length, 10.5 m. Peaks 1 = propane 2 = propylene 3 = isobutane 4 = n-butane 5 = isobutene 6 = butene-1 7 = rmns-butene-2 8 = cis-butene-2 9 = isopentane 10 = 3-methylbutene-l 11 = n-pentane 12 = pentene-1 13 = 2,2-dimethylbutene 14 = 2-methylbutene-l 15 = tnms-pentene-2 16 = cfsi)entene-2 17 = 2-methyl-butene-2 18 = 2,3-dimethylbutane 19 = 2-methylpentane 20 = 3-methylpentane 21 = 3-methylpen-tene-1 22 = 4-methylpentene-l 23 = c -4-methylpentene-2 24 = cyclopentane 25 = 2,3-dimethyl-butene-1 26 = fmns-4-methylpentene-2 27 = w-hexane 28 = cyclopentene 29 = 2-methylpentene-l 30 = hexene-1 31 = 2,4-dimethylpentane 32 = cis-hexene-3 33 = tnms-hexene-3 34 = 2-ethylbu-tene-1 35 = trans-hexene-2 36 = methylcyclopentane 37 = cis-methylpentene-2 38 = 2-methylpen-tene-2 39 = pisns-3-methylpentene-2 40 = methylcyclopentene-4 41 = 4-methylcyclopentene 42 = cw-3-methylpentene-2 43 = 2,3-dimethylpentane 44 = 2-methylheptane 45 = 2,3-dimethylbutene-2 46 = methylheptane 47 = cyclohexane 48 = C, olefin. Reprinted with permission from ref. 1.

Alkylation of isopentane with 2-butene at 10° in the presence of 100% sulfuric acid resulted in a 264% yield of alkylate based on the olefin (McAllister et al., 12). The theoretical yield for the simple alkylation reaction is 228%. Isobutane, hexanes (chiefly 2-methylpentane), nonanes, and decanes were formed. Destructive alkylation and hydrogen transfer occurred (Section III). 

Neohexane did not react when contacted with 2-butene at 10° in the presence of 100% sulfuric acid (McAllister el al., 12). Under similar conditions, alkylation of isohexane (a mixture of 2- and 3-methylpentane) yielded alkylate to the extent of 206% by weight of the 2-butene. It therefore appears that isoparaffins that contain tertiary carbon atoms are more susceptible to alkylation. 

Cyclamen homoaldehyde Cyclohexanone, 4-[(3,3-dimethylbicyclo [2.2.1] hept-2-yl) methyl]-2-methyl- 4-Cyclohexyl-4-methylpentan-2-one 3-Cyclopentene-1 -acetonitrile, 2,2,3-trimethyl- Decahydro-2,8,8-trimethylnaphthalene-2,4a-carbolactone trans-4-Decenal Dihydroisojasmone Dihydroterpinyl acetate Dimethyl bicycle [2.2.1] heptane-2-carbonitrile 1,5-Dimethylbicyclo [3.2.1] octan-8-one oxime 2,4-Dimethyl-3-cyclohexene carboxaldehyde Dimethyl-3-cyclohexene carboxaldehyde 1,3-Dimethyl-3-phenylbutylacetate 2,2-Dimethyl-3-phenylpropanol 4-Ethyl-a,a-dimethyl benzenepropanal 2-Ethyl-4-(2,2,3-trimethyl-3-cyclopenten-1-yl)-2-buten-1-ol Geranyl nitrile... 

Ziegler-Natta-type systems have been used in a variety of organic synthetic procedures, for example the regiospecific and stereoselective carbometallation of alkynyl silanes, Scheme 14, and for the alkylation of various alkynols. Scheme 15. The ethylation and methylation of the olefinic linkage in 3-buten-l-ol has been studied, here the alkenol was incorporated into a TiC and alane system. With Et2AlCl the major products obtained were hexan-l-ol, 3-methylpentan-l-ol, rram-3-hexen-l-ol, and butan-l-ol. EtgAl gave no alkylation products, but... 

D Anna et al. (2001a) have measured the rate coefficients for the branched hex-anals, 2-methylpentanal, 3-methylpentanal, 4-methylpentanal, 3,3-dimethylbutanal, and 2-ethylbutanal, with NO3 using relative rate techniques at 298 K with 1-butene as the reference reactant. Noda et al. (2002) have measured rate coefficients for NO3 + heptanal, octanal, and nonanal. The rate coefficients are shown in table IV-B-28, together with the atmospheric lifetimes for [NO3] 3 x 10 molecule cm. ... 

Contained approximately 0.8 ethyl branches. This value is not included in the comonomer incorporation. Operator 2. The average value for the 14 determinations is 5.09 with a standard deviation of 0.07 (relative precision at 2o of 2.7%). The average value for the 10 determinations is 4.85 with a standard deviation of 0.16 (relative precision at 2o or 6.8%). EB Ethene-butene 1 E4MP Ethene-4-methylpentane-l EH Ethene-hexane-1 EO Ethene-Octene-1 Reprinted with permission from M. De Footer, F.B. Smith, K.K. Dohrer, K.F. Bennett, M.D. Meadows, C.G. Smith, H.P. Schouwenaars and R.A. Geerards. Journal of Applied Polymer Science, 1991, 42, 2, 399. 1991, Wiley Interscience [59] ... 

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