(2,6-Dichloro-4-alkoxyphenyl)-(2,4-dichlorophenyl)methyl trichloroacetimidates: Protection of alcohols and carboxylic acids in solution or on polymer support

Synthesis

Volumn , Issue 21, 2009, Pages 3633-3641

  Kurosu, Michio ^a   Li, Kai ^a  

^a Department of Environmental and Radiological Health Sciences   (United States)

Author keywords

Alcohols and carboxylic acids; Diphenylmethyl ester derivative; Linker; Polymer bound; Protecting group

Indexed keywords

ALKOXYPHENYL; DEPROTECTION; ESTER DERIVATIVES; ETHER GROUP; LINKER; POLYMER SUPPORTS; PROTECTING GROUP; TRICHLOROACETIMIDATES; TRIFLUOROACETIC ACIDS;

CARBOXYLIC ACIDS; DICHLOROMETHANE; ESTERIFICATION; ESTERS; ETHERS; FLUORINE CONTAINING POLYMERS; POLYMERS;

ORGANIC ACIDS;

(2,6 DICHLORO 4 ALKOXYPHENYL)(2,4 DICHLOROPHENYL)METHYL TRICHLOROACETIMIDATE; ALCOHOL; CARBOXYLIC ACID; CHLORINE DERIVATIVE; POLYMER; TRICHLOROACETIMIDIC ACID; UNCLASSIFIED DRUG;

ARTICLE; CHEMICAL REACTION; DEPROTECTION REACTION; SYNTHESIS;

EID: 72049129708     PISSN: 00397881     EISSN: 1437210X     Source Type: Journal    
DOI: 10.1055/s-0029-1216974     Document Type: Article

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9. The ether 61 (Table 2) was stable under hydrogenation with 10% Pd/C in MeOH at 150 psi.
10. The imidate 4 did not react with tertiary alcohols under the same protection conditions for primary and secondary alcohols.
11. In our studies the free alcohol at the C2′-position of uridine derivatives are generally more reactive than those at the C3′-position. For example, tritylation (2 equiv) of 5t furnished the C2′,5′- ditritylated product.
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15. 2) and subsequent cleavage of the generated molecules on the polymer support.
16. 1H NMR spectra. However, so far, no good separation of the diastereomers of 6 was observed on TLC except in the case of 6e.
17. Detailed procedures for the cleavage of esters formed on resin 9 are given in reference 5.