A simple route to hexacyclo[4.4.0.02,4.03,10.05,8.07,9] decane (“barettane”) and pentacyclo[5.2.1.02,6.03,5.04,8] decane (“dihydrobarettane”)

Synthesis and chemistry of homocubanes, bishomocubanes, and trishomocubanes

“…be the case for attack by Rh(I) on substituted 1,3-bishomocubanes, bond cleavage occurs preferentially at the C(3)-C(4) tr-bond. These results are consistent with predictions based upon the results of empirical force field calculations.290,86 This hydrogenolysis reaction has been used to synthesize substituted tetracyclo-[5.2.1.02,6.04,8]decanes ["bisnorditwistanes"(115)] from the corresponding, substituted 1,3-bishomocubanes (Scheme 37) 84,85,87,88. …”

Three-Membered-Ring-Based Molecular Architectures

“…Upon heating to 500 °C, snoutene ( 836 ) undergoes an interesting automerization, as detected by appropriate labeling, which interchanges the two vinylic with the two cyclopropylic methyne positions . When irradiated with UV light, snoutene ( 836 ) reversibly rearranges to diademane ( 838 ). 220b, Thermally 104,546 and under silver(I) 547 or copper(I) 547 catalysis, diademane ( 838 ) rapidly rearranges to triquinacene ( 846 ), and this in turn undergoes photochemical isomerization to hexacyclo(4.4.0.0 2,4 .0 3,10 .0 5,8 .0 7,9 )decane ( 841 , barettane), along with four other (CH) 10 hydrocarbons (Scheme ) .…”

“…Diademane ( 838 ) also underwent isomerization to snoutene ( 836 ) under Au 0 , Au I , Pd 0 , or Rh I catalysis . Alternatively, barettane 841 was obtained from the bistosylhydrazone of tetracyclo[5.2.1.0 2,6 .0 4,8 ]decane-5,10-dione by 2-fold deprotonation with butyllithium and subsequent thermolysis 143 …”

“…The so-called stabilomer in the family of C 10 H 16 hydrocarbons, adamantane, was not detected. Not surprisingly, hydrogenolysis of barettane 841 furnished a single product formed by cleavage of the central single bonds in its two bicyclo[2.1.0]pentane moieties. 220b,

145

…”

Schemes and transformations in the (CH)2k series: Valence isomers of [8]- and [10]annulene

“…Y hexacyclo [4.4.0.02'5.03'9.043.07'10] decane (pentaprismane), Ealon, 1981 (35) Z tetracyclo [4.4.O.O2-6.O7,10]deca-3,8-diene (plerodactyladiene), Martin, 1981 (36b) cene (D) along with barretane (V). Later, this last isomer, V, was obtained by chemical synthesis (38) through a Bamford-Stevens reaction of a tosylhydrazone, and by improving the previous photochemical preparations (39). The synthesis of isomer X was achieved by photolysis of the Diels-Alder adduct of o-benzoquinone with benzvalene (34).…”