Dilithium acepentalenediide

In view of the high purity and thermal stability of dilithium acepentalenediide 32 -2Li+ [48], it is the most feasible precursor of other stable acepentalene metal derivatives and... 

Dilithium Acepentalenediide and Other Metal Complexes of Acepentalene... 

While some complexes of dihydroacepentalene derivatives have been reported some time ago [178-180], metal complexes of the unstable acepentalene (137), although they were the subject of DFT calculations [181], are still elusive. The acepentalene dianion (138) was obtained as its lithium salt in pure form by treatment of triquinacene (147) with BuLi/KOtBu/TMEDA giving 138 as its impure potassium salt, which was trapped with MegSnCl. The l,7-bis(trimethylstaimyl)-4,7-dihydroacepentalene (148) obtained was then treated with methyllithium, affording pure dilithium acepentalenediide (138-2Li+) (Scheme 10.52) [152]. 

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