Bongkrekic acid is an extremely potent toxin produced by the microorganism Pseudomonas cocovenenans. Synthetic routes ror preparing this compound have been sought in order to confirm its chemical structure and elucidate its biological mechanism. During a laboratory synthesis of bongkrekic acid, compound 1 was converted to compound 2 (U. Am. Chem. Soc. 1984, 106, 462-463). Propose an efficient synthesis for the conversion of 1 to 2. Bongkrekic acid The transformation above can be performed with some regent or combination of the reagents listed below. Give the necessary reagents in the correct order, as astring of letters (without spaces or punctuation, such as "EBF"). If there is more than one correct solution, provide just one