Tetramethyl-2,2,3,3-butane

Butan 2,2,3,3-Tetramethyl-V/la, 364 (Grign.-Wurtz-Reakt.) XIII/2a, 476 (Kha-rash-Reakt.)... 

Tetramethyl-zinn wird durch Elektrolyse von Methyljodid an einer Zinn-Kathode (in DMF/Tetrabutylammoniumperchlorat -1,92 V 67% SA) gewonnen. Dagegen wird bei der Elektrolyse von Athyl-, Propyl- Oder Butyljodid hauptsachlich Butan, Flexan bzw. Oc-tan gebildet6. 3-Jod-propansaure-nitrilliefertin 0,5 n Schwefelsiiure mit guten Ausbeuten wiederum Tetrakis- 2-cyan-athyl -zinn1 (65% d.Th.) Tetrakis-[2-cyan-athyl]-blei hin-gegen nur zu 13% d. Th.7. 

Dibrom-pentan kann bei -2,2 V in DMSO/Tetraathylammoniumbromid (Vorelek-trolyse ) in hoher Ausbeute zu 1,2-Dimethyl-cyclopropan reduziert werden (die Stereo-isomeren entstehen zu gleichen Teilen)1. In Methanol gelingt die quantitative Herstel-lung von 2-Hydroxy-2-methoxy-1,1 -dimethyl- bzw. 3-Hydroxy-3-methoxy-tetramethyl-cyclopropan aus l,3-Dibrom-2-oxo-3-methyl-butan bzw. 2,4-Dibrom-3-oxo-2,4-dime-thyl-pentan2. 

The chelate formation in lithium complexes 17 or 20 contributes to stabilization. Enhancement of kinetic acidity arises from the formation of pre-complexes 16 and 19, respectively. Here, already a dipole is induced and, in addition, proton exchange can proceed intramolecularly via a five- or six-membered ring. Despite these favourable features, the acidity of alkyl carbamates 15 is lower than those of the 1-proton in butane n-BuLi does not lead to deprotonation. In order to suppress carbonyl attack, a branched amino residue NR2 such as diisopropylamino (in Cb) or 2,2,4,4-tetramethyl-l,3-oxazolidin-3-yl (in Cby) is essential. A study on the carbenoid nature of compounds 17 was undertaken by Boche and coworkers. ... 

Tertiary alkyl radical Tertiary alkyl radical 1,5-Dibromo-3,3,4,4-tetramethyl butane... 

Manganese(III) acetate, 171 4-Methoxy-2,2,6,6-tetramethyl-l -oxopiperidinium chloride, 183 Palladium(II) chloride-Copper(II) chloride, 235 Samarium(II) iodide, 270 Tetrachlorotris[bis(l,4-diphenyl-phosphine)butane]diruthenium, 288... 

The compound is named as a tetramethyl derivative of butane it is 2,2,3,3-tetramethylbutane. 

Neopentyl glycol adipate Cyclohexane dimethanol adipate Tetramethyl cyclobutanediol adipate Neopentyl glycol succinate Butane-1,4-diol succinate Phenyl diethanolamine succinate Ethylene glycol sebacate Neopentyl glycol sebacate Ethylene glycol isophthalate Ethylene glycol phthalate... 

The cyclic voltammograms at vitreous carbon electrodes for 2-iodooctane, r-butyl bromide and -butyl iodide show two waves [e.g., -1.6 V and -1.8 V (see) for r-butyl bromide] indicating stepwise generation of alkyl radicals and carbanions. The products of large-scale electrolyses of r-butyl bromide (isobutane, isobutylene, 2,2,3,3-tetramethyl-butane) are indicative of the involvement of both radical and carbanion species214. 

The complex formed on addition of cuprous iodide to a solution of a lithium dialkylamide in ether or tetrahydrofuran is effective in the reductive coupling of allylic halides to give 1,5-dienes with preservation of stereochemistry. This method has been used5 for the stereospecific synthesis of all-trans-squalene and (E,Z,Z,E) squalene from (E,E)- and (Z,JE)-farnesyl bromides, respectively. In an attempted synthesis of (3S)-squalene-2,3-epoxide, 4-[(4R)-2,2,5,5-tetramethyl-l,3-dioxolan-4-yl]butan-2-one (1) and the phosphonium iodide (2) were prepared.6 Unfortu-... 

Me4phen = 3,4,7,8-tetramethyl-l, 10-phenanthroline 4,4 -dmbpy = 4,4 -dimethyl-2,2 -bipyridine dbbpy = 4,4 -di- r/-butyl-2,2 -bipyridine dtfmbpy = 5,5 -ditrifluoromethyl-2,2 -bipyridine dppm = bis-(diphenylphosphino)methane dppf = l,l -bis(diphenylphosphino)ferrocene i -BINAP = l,l -binaphthaline-bis(a-diphenylphosphine) chiraphos = 2,3-bis(diphenylphosphino)butane... 

Butan-al-saure Tetramethyl- -tert.-butylester E19a, 1244 (Oxidation)... 

Commercially important polyesters, e.g. poly[l-(2-ethylenyl)-2,2,6,6-tetramethyl-4-piperidinylbutane dioate] (146) [190] were synthesized from l-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidines and suitable dicarboxylic acids. Another polymeric HALS was prepared by transesterification of oligoesters of tetramethyl-butane-l,2,3,4-tetracarboxylate with 22,6,6-tetramethyl-4-hydroxypiperidine and 1,10-decanediol [191]. Compound 147 is a similar polyester type HALS. An ester-amide chain is created during esterification of 2-(2,2,6,6-tetramethyl-4-piperidinylamino)ethanol and dimethyl adipate [192]. 

In contrast to the above-mentioned monomers, l,4-bis(dimethylvinylsiloxy)butane in the presence of [RuHCl(CO)(PPh3)3] (1 mol%) under analogous conditions undergoes silylative coupling polycondensation to yield mainly siloxylene-alkylene-vinylene oligomers (isolated yield 60%). Only very small amounts of intramolecular reaction product (2,2,4,4-tetramethyl-3-... 

Cyclopemenyl)-1 -isopropyl- 2542 Bicyclol 1.1.0 butane 1-ten.-Bulyl-2-phenyl- 2395 l-Phenyl-2,2,4.4-tetramethyl- 33 Bicyclo 4.1.0 heptane... 

Isocyanurate-linked polymers can be formed by cyclotrimerization of diisocyanate intermediates under moderate temperature conditions (14). Compounds V and VI cyclotrimerize readily at room temperature upon addition of catalytic quantities of W,W,AT,N -tetramethyl-l,3-butane-diamine and allyl glycidyl ether, provided that atmospheric moisture is rigorously excluded. 

Tetramethyl-l,2-dioxolan wird durch Bestrahlung (A = 350 nm Benzol) in 2.2-Dimelhyl-oxiran (70% d.Th.), 2-0xo-butan (13% d.Th.) und Aeeton (7% d.Th.) hberfiihrt9. Bei den phenylierten Verbindungen sind die Ausbeuten ailgemein niedriger. 

Closely related to this synthesis of the eight-membered ring is a route to the four-membered ring compound l,l,3,3-tetramethyl-l,3-disilacyclo-butane (40). The final step is shown in Eq. (10) ring closure is brought about with Mg in diethyl ether with a yield of 70% ... 

Tetramethyl-CH is shown in Figure 4. The similarity of the product distributions is apparent. Again, high ratios of isobutane to n-butane and of MCP to CH are observed. These results show that the composition of the product is essentially independent of the reactant structure. The ring yield in each case exceeds 80 mole %. 

AI3-23740 Benzene, 1, T-(1,1,2,2-tetramethyl-1,2-ethanediyl)bis-Bibenzyl, a,a,a, a -tetramethyl- Butane, 2,3-dimethyl-2,3-diphenyl-a,a -Dicumyl 2,3-Dimethyl-2,3-diphenylbutane EINECS 217-568-2 NSC 34859 Perkadox 301,1 -(1,1,2,2-Tetramethylethylene)di-benzene. Akzo Chemie. 

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