Doxaprost, an orally active bronchodilator patterned after the natural prostaglandins , is synthesized in the following series of reactions starting with ethyl 2-oxocyclopentanecarboxylate. Except for the Nef reaction in Step 8, we have seen examples of all other types of reactions involved in this synthesis.
Q. Describe experimental conditions to bring about Step 7 and account for the fact that the trans isomer is formed in this step.
Extracted text: COOEt СООН COOEt (CH,),COOCH (CH,),COOH Ethyl 2-oxocyclo- pentanecarboxylate Br (CH,),COOH (CH,),COOH O (CH,),COOH Nef (CH2),COOCH3 reaction (CH2),COOCH3 n(CH2),COOCH, CH,NO, H aCH),COOCH3 H. 10 (CH2),COOH H (CH),COOH H (CH,),CH3 (CH2),CH3 (CH,),CH3 H. H HƠ CH3 Doxaprost (an orally active bronchodilator)