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Cleavage of trityl ethers

Because of the high stability of the triphenylmethyl carbocation, the reductive ether cleavage of trityl ethers with EtySiH/trimethylsilyl triflate (TMSOTf) is highly successful. This reaction even occurs in the presence of highly reactive sugar ketals, leaving the ketals intact (Eq. 126).269... [Pg.50]

Cleavage of trityl ethers is accomplished by acid hydrolysis. Use of the mono- or di-methoxy analogs increase the acid lability of the trityl ethers, but none of the trityl ethers is stable enough to withstand normal glycosylation conditions, and they are only used as intermediates to construct building blocks to be used in subsequent oligosaccharide syntheses. [Pg.79]

Hydiobiomic acid Cleavage of ethers 8. 1, 11/2 2, 31 4, 18 with simultaneous replacement of nitro groups by bromine 8. 5, 411 Cleavage of trityl ethers s. 2, 249 3,10 Hydroxycarboxylic acids from methoxynitriles s. 2, 236 HBr ROR -V ROH... [Pg.8]

By use of HgO in place of Cd-carbonate, to neutralize the HC1 set free during the reaction, cleavage of trityl ethers is avoided.—E 5-Trityl D-arabinose diethyl mereaptal —> 5-trityl D-arabinose. Y 76%. N. W. Bristow and B. Lythgoe, Soc. 1949, 2306.)... [Pg.335]

Detritylation. YbfOTflj catalyzes cleavage of trityl ethers and V-tritylamines in THF (containing one equiv of water) at room temperature. [Pg.487]

BE3 -OEt2 easy-to-handle and convenient source of BF3 Lewis acid catalyst promotes epoxide cleavage and rearrangement, control of stereoselectivity BF3 MeOH esterification of aliphatic and aromatic acids cleavage of trityl ethers)... [Pg.27]

Cleavage of Ethers. In aprotic, anhydrous solvents, BFs-MeOH is useful for the cleavage of trityl ethers at rt. Under these conditions, O- and Ai-acyl groups, 0-sulfonyl, W-alkoxycarbonyl, O-methyl, O-benzyl, and acetal groups are not cleaved. [Pg.32]

The tritylation of alcohols under neutral conditions has been achieved using p-methoxybenzyl trityl ether in the presence of DDQ. A selective cleavage of trityl ethers by CBr4-MeOH has been attributed to the formation of traces of HBr. Ceric ammonium nitrate on silica gel rapidly cleaves trityl and mono and di-methoxytrityl ethers whereas CeCb-Nal in refluxing acetonitrile effects the selective cleavage of trityl and dimethoxytrityl ethers under neutral conditions. ... [Pg.92]

Bismuth(III) chloride in acetonitrile has been reported as a catalyst for the selective and efficient cleavage of trityl ethers. THP ethers, tert-butyloxicarbonyl (BOC) group, tert-butyldiphenylsilyl (TBDPS) and p-methoxybenzyl (PMB) esters were resistant to these conditions [100]. [Pg.46]

Cleavage of trityl ethers with Na/NH3 Tetr Lett (1972) 2549 Preparation of substituted trityl ethers JOC (1972) 956... [Pg.64]

Hydrobromic acid Cleavage of trityl ethers selective s. 12, 25 O-Deacetylation... [Pg.19]

Fig. 8.122 Examples of selective cleavage of trityl ethers catalyzed by lnBr3 or InC. ... Fig. 8.122 Examples of selective cleavage of trityl ethers catalyzed by lnBr3 or InC. ...
See other pages where Cleavage of trityl ethers is mentioned: [Pg.230]    [Pg.260]    [Pg.260]    [Pg.261]    [Pg.44]    [Pg.81]    [Pg.260]    [Pg.261]    [Pg.740]    [Pg.60]    [Pg.17]    [Pg.300]    [Pg.46]    [Pg.307]    [Pg.366]    [Pg.367]    [Pg.368]    [Pg.369]   
See also in sourсe #XX -- [ Pg.415 ]

See also in sourсe #XX -- [ Pg.415 ]



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Cleavage of ethers

Ethers cleavage

Trityl

Trityl cleavage

Trityl ethers, cleavage

Tritylation

Trityls

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