Abstract
Pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dione was synthesized from the cyclopentanone in good overall yield(60%). Cyclopentanone ethylene ketal(Ⅰ) was brominated with pyridinium bromide perbromide, and the brominated ketal(Ⅱ) was converted to the dimer of cyclopentadienone ethylene ketal(Ⅲ). The ethylene ketal(Ⅲ) was again converted to the dicyclopentadiene-1,8-dione(Ⅳ). Finally, the pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dione(Ⅴ) was synthesized from the dicyclopentadilene-1,8-dione(Ⅳ) by photochemical cyclization.
Cyclopentanone을 출발 물질로 하여 60%의 좋은 총 수득률로 pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dion을 합성하였다. Cyclopentanone 으로부터 그의 ethylene ketal(I)을 합성하여 pyridinium bromide perbromide로서 브롬화시키고 브롬화 ketal(II)을 다시 dehydrobromination 시켜 cyclopentadienone-ethylene ketal의 dimer를 합성하였다. Ethylene ketal의 dimer(III)를 다시 가수분해시켜 dicyclopentadiene-1,8-dione(IV)을 합성하고 이 diketone(IV)을 photochemical cyclization에 의하여 pentacyclo ($5,3,0,0^{2,5},06{3,9},0^{4,8})-decane-6,10-dione(V)을 합성하였다.