205931-08-4Relevant articles and documents
Bargellini condensation of coumarins. Expeditious route to o-carboxyvinylphenoxyisobutyric acids and application to the synthesis of sesquiterpenes helianane, heliannuol A and heliannuol C
Biswas, Bidyut,Sen, Prabir K.,Venkateswaran, Ramanathapuram V.
, p. 12026 - 12036 (2008/03/13)
The direct Bargellini condensation of coumarins involving reaction with chloroform and acetone in the presence of aqueous sodium hydroxide furnished o-carboxyvinylphenoxyisobutyric acids in good yields. The utility of this new useful protocol was demonstrated by the transformation of the three diesters 9b, 9f and 9g to the sesquiterpenes helianane 4, heliannuol A 2 and heliannuol C 3, respectively.
Bargellini condensation of coumarins. Expeditious synthesis of o-carboxyvinylphenoxyisobutyric acids
Sen, Prabir K.,Biswas, Bidyut,Venkateswaran, Ramanathapuram V.
, p. 8741 - 8743 (2007/10/03)
Condensation of coumarins with chloroform and acetone in the presence of a base furnished o-carboxyvinylphenoxyisobutyric acids in good yields. The diacid 7a was transformed in a few high yielding steps to the marine sesquiterpene helianane underscoring t