Ether, tert-BUTYL phenyl

Ether, tert-butyl phenyl, 41, 91 Etherification of cholestanol with diazomethane, 41, 9... 

Ethanol, 2-nitro-, 41, 67 conversion to nitroethylene, 41, 71 Ether, tert-butyl phenyl, 41, 91 Etherification of cholestanol, 41, 9 with diazomethane, 41, 9 3-Ethoxy-2-cyclohexenone, 40, 41 reduction to 2-cyclohexenone, 40, 14... 

PHENYL tert-BUTYL ETHER (Ether, [Pg.91]

Bromobenzene Benzyne tert-Butyl phenyl ether... 

Potassium tert-butoxide reacts with halobenzenes on heating in dimethyl sulfoxide to give tert-butyl phenyl ether. 

The Williamson ether synthesis cannot be used to prepare tert-butyl phenyl ether. 

I5 phenyl ethyl ether 37 (Crphenyl)ethyl tert-butyl ether (tentative) 62 C2-benzofuran... 

Triton X-100 ([4-(l,l,3,3-Tetramethyl-butyl)-phenyl]-deca(ethyleneglycol)ether tert-C8[Pg.227]

Substituted cyclohexanones, bearing a methyl, isopropyl, tert-butyl or phenyl group, give, on deprotonation with various chiral lithium amides in the presence of chlorotrimethylsilane (internal quench), the corresponding chiral enol ethers with moderate to apparently high enantioselec-tivity and in good yield (see Table 2)13,14,24> 29 36,37,55. Similar enantioselectivities are obtained with the external quench " technique when deprotonation is carried out in the presence of added lithium chloride (see Table 2, entries 5, 10, and 30)593. 

The first variant works with isobutane as the hydroperoxide precursor, which is oxidized to TBHP by molecular oxygen. During the epoxidation of propene, TBHP is transformed to tert-butanol, which is converted to methyl tert-butyl ether. The second procedure employs ethylbenzene, which is oxidized by molecular oxygen to phenyl ethyl hydroperoxide, which transfers an oxygen to propene and so is reduced to phenylethanol. This by-product of the process is converted to styrene, a versatile bulk chemical. 

The method presented is essentially that described by Lawesson and Yang.2 Phenyl tert-butyl ether has been prepared by acid-catalyzed condensation of isobutylene and phenol3 and by reaction of diphenyliodonium chloride with potassium feri-butoxide.4... 

A hitherto unpublished preparation of diazomethane is given on p. 16. The starting material is the commercially available bis-(N-methyl-N-nitroso)-terephthalamide, and the procedure conveniently affords 0.76 to 0.86 mole of ethereal diazomethane. Ozonization in polar solvents is illustrated by two preparations (pp. 41 and 46). Many other unusual and interesting preparations are included, such as ruthenocene (p. 96), N,N-di thyltri-chlorovinylamine (p. 21), phenyl tert-butyl ether (p. 91), and tetramethylammonium 1,1,2,3,3-pentacyanopropenide (p. 99). 

Entry 9 in Table 3.13 is an example of a safety-catch linker, which requires activation by TFA-mediated cleavage of a tert-butyl ether. The unactivated 2-(tm-butoxyj-phenyl esters are cleaved by amines 700 times more slowly than the corresponding 2-hydroxyphenyl esters [289]. A similar linker has been described [290], in which a benzyl ether is used instead of a ferf-butyl ether. Activation of this linker by debenzy-lation was achieved by treatment with HF or HBr/TFA [290]. 

A solution of 561 mg of 2-[3(S)-amino-2(R)-hydroxy-4-phenylbutyl]-N-tert-butyl-decahydro-(4aS,8aS) -isoquinoline-3(S)-carboxamide and 372 mg of N-(benzyloxycarbonyl)-L-asparagine in 20 ml of dry tetrahydrofuran was cooled in an ice/salt mixture. 189 mg of hydroxybenzotriazole, 161 mg of N-ethylmorpholine and 317 mg of dicyclohexylcarbodiimide were added and the mixture was stirred for 16 h. The mixture was then diluted with ethyl acetate and filtered. The filtrate was washed with aqueous sodium bicarbonate solution and sodium chloride solution. The solvent was removed by evaporation and the residue was chromatographed on silica gel using dichloromethane/methanol (9 1) for the elution to give 434 mg of 2-[3(S)-[[N-(benzyloxycarbonyl)-L-asparaginyl]amino]-2(R)-hydroxy-4-phenyl butyl]-N-tert-butyl-decahydro-(4aS,8aS)-isoquinoline-3(S)-carboxamide as a white solid from methanol/diethyl ether. 

O-Arylation of alcohols or phenols cannot be performed by copper diacetate-catalyzed reactions using aryllead triacetates as the source of the aryl ligand. However, Dodonov et at. reported that tetraphenyllead reacts with primary and secondary alcohols in the presence of copper diacetate to afford the derived O-phenyl ethers in moderate yields ranging from 1.25 to 1.8 mol. of ether per mole of the lead reagent (Equation (100)). Phenol and tert-butyl alcohol afforded lower yields of the ethers (0.72-0.95 mole per mole of the lead reagent).117... 

To date, only a few examples of laboratory preparative-scale processes based on purified enzyme have been reported. Several studies have focused on the small-scale implementation of processes associating a new co-factor regenerating system, enzyme immobilization, membrane reactor, continuous substrate feeding, or resin-based SFPR with various results [110], Using the outstanding stabihty of PAMO, a 200 ml biotransformation of 5g/l phenyl cyclohexanone by an engineered mutant under two-Hquid phase conditions using methyl tert-butyl ether as solvent was described [102]. 

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