Oxirane 2-butyl-2-methyl

Oxirane, methyl-, homopolymer. See Polypropylene glycol Oxirane ((methylphenoxy)methyl)-. See Orthocresyl glycidyl ether Oxirane, methyl, polymer and oxibane, butyl ether. See PPG-2-buteth-3 Oxirane, methyl-, polymer with oxirane, 1/4-dimethyl-1,4-bis(2-methylpropyl)-2-butyne-1,4-diyl ether CAS 182211-02-5... 

There are other commercial processes available for the production of butylenes. However, these are site or manufacturer specific, eg, the Oxirane process for the production of propylene oxide the disproportionation of higher olefins and the oligomerisation of ethylene. Any of these processes can become an important source in the future. More recentiy, the Coastal Isobutane process began commercialisation to produce isobutylene from butanes for meeting the expected demand for methyl-/ rZ-butyl ether (40). 

Oxirane Process. In Arco s Oxirane process, tert-huty alcohol is a by-product in the production of propylene oxide from a propjiene—isobutane mixture. Polymer-grade isobutylene can be obtained by dehydration of the alcohol. / fZ-Butyl alcohol [75-65-0] competes directly with methyl-/ fZ-butyl ether as a gasoline additive, but its potential is limited by its partial miscibility with gasoline. Current surplus dehydration capacity can be utilized to produce isobutylene as more methyl-/ fZ-butyl ether is diverted as high octane blending component. 

The patterns of regio- and stereoselectivities become more complex in disubstituted oxiranes. Beginning with 2,2-disubstituted oxiranes, attack is always at the accessible C-atom. In terms of substrate enantioselectivity, it was found that 2-butyl-2-methyloxirane (2-methyl-1,2-epoxyhexane, 10.43, R = Bu) was hydrolyzed with a preference for the (5)-enantiomer. This substrate enantioselectivity was lost for branched analogues, namely 2-(/er/-bu-tyl)-2-methyloxirane (10.43, R = /-Bu) and 2-(2,2-dimethylpropyl)-2-meth-yloxirane (10.43, R = (CH3)3CCH2) [124], Thus, it appears that the introduction of a geminal Me group suppresses the enantioselectivity seen with branched monoalkyloxiranes, and reverses it for straight-chain alkyloxiranes. 

The chlorohydrins show different rates of cyciization, reflecting the steric hindrance of residue R. The most vigorous reaction is observed in the case of (S)-2-chloropropan-l-ol (R = CH3) only 30°C at 100 mm is required. For (R)-isopropyloxirane, the temperature of the bath is raised slowly to 50°C, and after 40 min to 60°C, while the pressure is reduced to 50 ram for an additional 5 min. For the higher boiling oxiranes, e.g., (R)-isobutyloxirane and (S)-sec-butyl-(R)-oxirane [(2R,3S)-3-methyl-1,2-epoxybutane] , the temperature is raised slowly to 60°C within 1 hr, while the pressure is reduced carefully to 30 mm. 

Pentanoate Ethyl 2-Fluoro-3-hydroxy-3-methyl- ElOb, 454 (Ketone + F-CH2-COOR) Propanoatc tert.-Butyl 2-Fluoro-2-methoxy- ElOa, 495 (Na F) 2-Propanole 3-Fluoro-l-(2-tetra-hydropyranoyloxy)- ElOb, 152 (Oxirane + R3N H,F3)... 

Dccyloxy-phenyl) 4-j[2-(3,3-Dimethyl-butyl)-oxiran-2-yl]-fliioro-methyl - ElOb, 89 (OH - F)... 

Standard Oil of California added the petrochemicals of Gulf Oil, purchased in 1984, to its subsidiary Chevron Chemical. Other United States petrochemical producers took advantage of special circumstances. Amoco was served by a strong terephthalic (TPA) base and its good performance in polypropylene Arco, by its Lyondell subsidiary in Channelview, Texas, and by its development of the Oxirane process through which propylene oxide could be produced by direct oxidation with styrene as a coproduct. The process also led to MTBE (methyl tertiary-butyl ether), the antiknock agent used as a substitute for tetraethyl lead. 

A homogeneous catalytic process, developed by Oxirane, uses a molybdenum catalyst that epoxidizes propylene by transferring an oxygen atom from tertiary butyl hydroperoxide. This is shown by 8.28. The hydroperoxide is obtained by the auto-oxidation of isobutane. The co-product of propylene oxide, /-butanol, finds use as an antiknock gasoline additive. It is also used in the synthesis of methyl /-butyl ether, another important gasoline additive. The over-... 

Ethen 2-Brom-l-butyloxy- V/4, 752 Furan 2-Brommethyl-5-methyl-tetrahydro- Vl/3, 537 Oxiran 3-Brom-2-tert.-butyl-E14a/3, 29 (Br2CH —CO—R/ NaOH Red.)... 

Peroxid tert.-Butyl-(2-hydroxy-ethyl)- VI/Ia,l, 386 E13/1, 376/378 (Oxiran 4- R-0 - OH) Propan l,l-Dimethoxy-2-hydroxy-2-methyl- E14a/I. 766 (R2CH-CHO + R-OH/ Elektrol.)... 

Chlor-5-methyI- E2lb, 1477 [(H3C)2CH-CHO H2C = CH - CHC1 - B(OR)2] Oxiran (Z)-3-tert.-Butyl-2-chlor-2-methyl- E14a/3, 55 (Epoxigenier.) Propan 1-Allyloxy-l -chlor-2-methyl-EI4a/3, 37 (OR - Cl)... 

Benzyl-1 -(3-hydroxy-propyl)- E16a, 487 (R2N —NO —Red.) 2-(2-Hydroxy-butyl)-l-phenyl- El6a, 601 (R-NH-NH2 + Oxiran) 2-(2-Hydroxy-2-methyl-propyl)- 3 -phenyl- E16a, 601 (R-NH-NH2 + Oxiran) (4-Isopropyloxy-benzyl)- E16a, 432 (Hydrazin-Alkyl.) (4-Propyloxy-benzyl)- E16a, 432 (Hydrazin-Alkyl.)... 

CuHjjOj (Continuation) Decansaure 2-Methyl E19a, 651 (Carbonsiiure + En) E21a, 839f./846 (CO-NR2 - COOH), 1025 [C(OR) = NR - COOH] 1,3-Dioxolan 5-Butyl-2,2,4,4-tetramethyl- E14a/1, 291 (Keton -I- Oxiran)... 

Much attention has been paid to the mechanism via the carbonium ion intermediate. Detailed studies have been performed on the dependence on the migrating group. In the BFs-catalyzed rearrangement of the 1,1-disubstituted oxirane 100 (Eq. 120), ° it has been proved that the H atom cis to the methyl group migrates as a consequence of the interaction between the bulky tert-butyl and the OBF3 group. In this case, 102 is the favored conformer. 

When chloromethyl p-tolyl sulfoxide (102 R = p-tolyl) is treated with carbonyl compounds (103) and potassium t-butoxide in t-butyl alcohol ether, (p-tolylsulfmyl)oxiranes (104) are directly formed. Chloromethyl methyl sulfoxide (102 R = Me) exhibits the same behavior (Scheme 29). These reactions proceed with high stereoselection at the position a to the sulfmyl group. The stereochemical course proposed for the attack of the carbanion of an a-halo sulfoxide on a carbonyl compound is shown in Figure 4. ... 

Bei der Behandlung von ds-bzw. trans- 2,3-Di-tcrt.-butyl-oxiran mit gasformigem Bortri-fluorid in Tetrachlormethan bei 25° werden 2,2-Dimethyl-propanal und 2-Methyl-2-bu-ten erhalten72 ... 

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