Polymer-supported O-benzyl and O-allylisoureas: Convenient preparation and use in ester synthesis from carboxylic acids

Organic Letters

Volumn 5, Issue 6, 2003, Pages 853-856

  Crosignani, Stefano ^a   White, Peter D ^b   Steinauer, Rene ^c   Linclau, Bruno ^a  

^a UNIVERSITY OF SOUTHAMPTON   (United Kingdom)

^b Merck Biosciences Ltd   (United Kingdom)

^c Merck Biosciences AG   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

ALCOHOL; BENZYL DERIVATIVE; CARBOXYLIC ACID DERIVATIVE; COPPER; CYANAMIDE; ESTER; METHYL GROUP; POLYMER; REAGENT; RESIN; SOLVENT; UREA DERIVATIVE;

ARTICLE; CATALYSIS; EVAPORATION; FILTRATION; PURIFICATION; SYNTHESIS;

EID: 0141451864     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0275062     Document Type: Article

References (17)

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15. When commercial carbodiimide 1 was used as a starting material, the products obtained after the esterification reactions were contaminated by unknown products. The authors believe that the harsh conditions employed in the commercial preparation of 1 are responsible for this, and that the use of a mild dehydration step to obtain carbodiimide 1 is essential for obtaining polymer-supported isoureas that do not suffer from leaching.
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17. In our experience, using 0.175 mmol of carboxylic acid and 2 mL of THF, the maximum temperature achievable is around 130°C.