Synthesis and reactions of 9,10,11-triptindantrione and some other functionalized tribenzo[3.3.3]propellanes (9H,10H-4b,9a-([1,2]benzenomethano)indeno[1,2-a]indenes)

Paisdor B, Kuck D. Synthesis and reactions of 9,10,11-triptindantrione and some other functionalized tribenzo[3.3.3]propellanes (9H,10H-4b,9a-([1,2]benzenomethano)indeno[1,2-a]indenes). Journal of Organic Chemistry. 1991;56(15):4753-4759.A new and efficient route to the tribenzo[3.3.3]propellane 1 (triptindan) and to some interesting derivatives such as 9-triptindanone (13) and 9,10,11-triptindantrione (3) has been developed. The propellane framework of 13 is accessible from 1,3-indandione in only two steps. Triketone 3, a versatile substrate with formal C3-upsilon molecular symmetry, is obtained from 13 in two further steps. First examples are presented for reactions of 3 leading to more complex benzoannelated centropolyquinanes (centropolyindans)