A Convenient Synthesis of the Cubane System

Synthesis and chemistry of homocubanes, bishomocubanes, and trishomocubanes

“…However, in the case of 127 and 129, the C(6) carbonyl substituent, which is capable of conjugative stabilization of a carbanionic transition state, might be expected to promote (contrathermodynamic) scission of the C(4)-C(5) a-bond in each of the react a n t~. '~ The results of empirical force field calculations provide additional theoretical insight that supports these s u g g e s t i~n s .~~~~~~ Thermal ring opening of 4-methoxypentacyclo-[5.3.0.02~5.03~9.04~8]decan-6-ones110 and 134 has been studied by using flash vacuum pyrolysis techniques. Thus, when 110 and 134 were heated in the gas phase at 400 OC/O.O35 Torr, cleavage of a cyclobutane ring in both 110 and 134 occurred, thereby affording the corresponding dienes (135 and 136, respectively).11i82 Cage opening of 110 and 134 could also be accomplished by treating a toluene solution of either substrate with hydrogen chloride gas.…”

Cubane: 50 Years Later

“…They developed the first highly selective C−H bromination, iodination, and chlorination of cubane through use of phasetransfer conditions. Starting from cubane (1), the authors discovered that they could obtain brominated (38), iodinated (39), and chlorinated (40) cubanes in high yields through the employment of the respective halomethane (Scheme 10). 52 3.1.2.…”

Reciprocal polyhedra and the Euler relationship: cage hydrocarbons, CnHn and closo-boranes [BxHx]2−

“…An elegant modification of this procedure has been reported by Pettit [ 13 ] who used (cyclobutadiene)Fe(CO) 3 , ( 30 ), as the source of one of the square faces ( Scheme 5 ). Once again, as in Eaton's procedure, two Favorski ring contractions were used to obtain the cubane skeleton, first in the form of the dicarboxylic acid 33 which on subsequent decarboxylation gave 10 .…”