R-Butylphenols

Blends of enzymatically synthesized poly(bisphenol-A) and poly(p-r-butylphenol) with poly(e-CL) were examined. FT-IR analysis showed the expected strong intermolecular hydrogen-bonding interaction between the phenolic polymer with poly(e-CL). A single 7 was observed for the blend, and the value increased as a function of the polymer content, indicating their good miscibility in the amorphous state. In the blend of enzymatically synthesized poly(4,4 -oxybisphenol) with poly(e-CL), both polymers were miscible in the amorphous phase also. The crystallinity of poly(e-CL) decreased by poly(4,4 -oxybisphenol). 

Immortal polymerization of epoxides with la and an alcohol is also accelerated by co-use of bulky Lewis acid 2a. The polymerization of PO with la/2-propanol system ([PO]/[la]/[2-propanol] = 1000/1/49) in the presence of 2a ([PO]/[2a] = 1000/1) proceeds rapidly to achieve 86% conversion in 1.5 h, while the polymerization in the absence of 2a requires 380 h to reach 84% conversion (Table 1). The polyether produced in the presence of 2a has an of 900 gmoP and an MJM of 1.10, which indicates that almost all of la and 2-propanol participate in the initiation of the polymerization. Other protic chain-transfer reagents, such as methanol, benzyl alcohol, and 4-/ r/-butylphenol, are also applicable to the high-speed immortal polymerization to give similar results as 2-propanol. As a substrate, ECH is also employable. Polymerization of ECH ([EGH]/[la]/[2-propanol]/[2a] = 1000/1/49/1) gives a polymer with and/n of 1100gmol close to the value estimated from the conversion and [PO]/([la] + [2-propanol]) ratio, and a narrow M IM of 1.10, while the conversion is lower than the case of PO. 

Oxidation of 44 is completely inhibited by the addition of a small amount of 2,4,6-tri-r-butylphenol. Consequently, the oxidation of the Si—Si bond with oxygen displays the following features 1) a Si—Si bond which is either angle-strained or substituted with more than two fluorine atoms is easily oxidized 2) a radical mechanism is operative 3) the insertion of oxygen into the Si—Si bond proceeds stereospecifically62. Incorporation of molecular oxygen was also observed in the direct photolysis of the cyclopolysilanes 80 and 81 (equations 88 and 89)91. 

When two polymeric systems are mixed together in a solvent and are spin-coated onto a substrate, phase separation sometimes occurs, as described for the application of poly (2-methyl-1-pentene sulfone) as a dissolution inhibitor for a Novolak resin (4). There are two ways to improve the compatibility of polymer mixtures in addition to using a proper solvent modification of one or both components. The miscibility of poly(olefin sulfones) with Novolak resins is reported to be marginal. To improve miscibility, Fahrenholtz and Kwei prepared several alkyl-substituted phenol-formaldehyde Novolak resins (including 2-n-propylphenol, 2-r-butylphenol, 2-sec-butylphenol, and 2-phenylphenol). They discussed the compatibility in terms of increased specific interactions such as formation of hydrogen bonds between unlike polymers and decreased specific interactions by a bulky substituent, and also in terms of "polarity matches" (18). In these studies, 2-ethoxyethyl acetate was used as a solvent (4,18). Formation of charge transfer complexes between the Novolak resins and the poly (olefin sulfones) is also reported (6). 

In structures such as 2,6-di-r-butylphenol, in which steric hindrance prevents hydrogen bonding, no bonded hydroxyl band is observed, not even in spectra of neat samples. 

An interesting example that illustrates the role of activation parameters in providing an understanding of the reaction mechanism was reported recently.47 A mthenium(III) terpyridine-4 -carboxylate complex, RuraCOO, reacts with tri-A / r-butylphenol in acetonitrile according to Scheme 8.10. 

The nature of the cation (K+ or Na+) in hydroxides has been found to affect the temperature plot of the equilibrium constants of the reaction of KOH and NaOH with 2,6-di-r-butylphenol (ArOH). The nature of the cation in the resulting phenoxides ArOK or ArONa is a factor determining the kinetics of the addition of ArOH to CH2=CHC02Me. Two different kinetic schemes have been proposed to describe the transformation of ArOH in the presence of ArONa or ArOK.137... 

Copolymerization of 4-bromo-2,6-dimethylphenol with 2,4,6-trimethylphenol, 4-t-butyl-2,6-dimethylphenol, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 4-hydroxy-3,5-dimethylbenzyl alcohol and a 4-substituted-2,6-di-r-butylphenol are discussed269. 

Bis[morpholino] tellurium dichloride in dichloromethane oxidized hydroquinones quickly to quinones, thiols quickly to disulfides, and 2,6-di-r-butylphenol slowly to a dipheno-quinone. The by-products are elemental tellurium and morpholine hydrochloride2. 

Hart and Cassis, Jr. utilized the dechlorination with Raney alloy and alkali in the synthesis of 2,6-di-r-butylphenol from 4-bromo- or 4-chlorophenol as starting mate-... 

Urethanes analogous to the amides of the previous section undergo similar deprotonation followed by alkylation and condoisation reactions. For example, 2,4,6-tri-r-butylphenol may be converted into the corresponding urethane which can be further functionalized (equation 32). N-Carbomethoxy-3-pyrroline has been convoted into both the trail pheromone for the Pharaoh ant and gq)hyrotoxin 223 by using regiospecific alkylations (Scheme 3). ° Similar tqjproaches were used in the preparation of the natural product supinidine. Piperidines also have been alkylated via the r-BOC-protected amines. ... 

Thallium trifluoroacetate has not enjoyed widespread use as a reagent for quinone synthesis, possibly because it is still a relatively new reagent but more probably because of its toxicity. One example of its use lies in the synthesis of metacyclophanes and related compounds as reported by Tashiro et al Thus the r-butylphenol (59) gave the bisquinone (61), while the phenol (60) afforded the monoquinone (62). An alternative and more practical synthesis of the bisquinone (61) for large scale work involved dealkylation to afford the bisphenol (63) which was then treated with sodium nitrite to give the bisoxime (64). Hydrolysis of the bisoxime did not give the quinone (61), but it could be obtained by zinc/acetic acid reduction of the bisoxime followed by oxidation with nitric acid (Scheme 13). 

The reaction of the 1,3-dithiolium cation 138 with 2,6-di-/i r/-butylphenol gave the dithiafulvene 139 in 23% yield (Equation 2) <2005JA8835>. 

We have also prepared the 0-bonded silanetriol (2,4,6-rBu3C6H2)OSi(OH)3 (18) starting from 2,4,6-tri-r-butylphenol (Scheme 4) [27]. However, the synthesis of other O-bonded silanetriols proved to be difficult due to the ready cleavage of the Si-O(aryl) bond... 

Preparation. Dialkyl acetals of DMF are generally prepared by transacetal-ization of the dimethyl or diethyl acetal, but this reaction is not useful in the case of the di-r-butyl acetal. Replacement of one methoxy group of DMF dimethyl acetal occurs on refluxing in f-butyl alcohol conversion to the di-f-butyl acetal is effected in the presence of 2,4,6-tri-r-butylphenol (equation I). 

Aminodehydroxylation, 152-153,398 2-Amino-3,6-di-r-butylphenol, 406 7-Aminofurazano[3,4-d] pyrimidines, 281 4-Amino-3-hydrazino-5-mercapto-l, 2,4-triazole, 19... 

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