Asterane

Intramolecular Photochemical Cycloaddition of Nonconjugated Olefins

“…The dichloroquinone CXCI gave a nearly colorless dimer (3%) of undetermined structure on irradiation (6). Quinones CXCII-CXCIV failed to give any dimer on irradiation through Pyrex either in solution or as crystals, while CXCV gave only an open trans dimer (18).…”

“…Another report indicated that CLXXVII gave only polymer and hydroquinone on irradiation (18 CLXXXII (44) (and CLXXXI and CLXXXII) are really different has not been resolved (18). in addition to the oxetane CLXXXVI (6,18,22,24) (Eq 55). XXXVIII are possible precursors to CLXXXIV and CLXXXV, rexpectively (57).…”

Tetraasteran, Pentacyclo[6.4.0.02,7.04,11.05,10]‐dodecan

“…-!-Phenyl-2,2-dichlorcyclopropan (2 j + 1.83 (9) + 1.70 [c] l-Athoxy-7,7-dichIornorcaran (3) + 1.65 ( 6 ) +1.28 [b] l-Athoxy-R,X-dichiorl-Athoxy -9,9-dichlor-bicyclo[5.1 .O]octan ( 4 ) f1.65 ( ( 4 ) in 9-10 "/, Ausbeute neben anderen Produkten zuganglich[''.…”

Dimerization of Pyramidalized 3,4,8,9‐Tetramethyltetracyclo [4.4.0.03,9.04,8]dec‐1(6)‐ene to a Hydrocarbon Featuring Four Cyclohexane Rings in Boat Conformations

“…camphor and other norbornane derivatives) 11. Some notable exceptions with frozen boat cyclohexanes, featuring a H–H flagpole interaction, are the asteranes, such as tetracyclo [3.3.1.0 2,8 .0 4,6 ]nonane (triasterane; 9 )12 tricyclo[3.1.1.1 2, 4 ]octane (diasterane; 10 ),12d, 13 and pentacyclo[6.4.0.0 2,7 .0 4,11 .0 5,10 ] dodecane (tetraasterane; 11 ),12a,d, 14, 15 and tetracyclo[5.3.1.1 2,6 .0 4,9 ]dodecane (iceane; 12 ),16 a polycyclic compound featuring two chair and three boat cyclohexane rings (Figure 2). Interestingly, the cyclobutane rings of these polycyclic compounds can be either planar, as in 7 and 11 , or puckered as in 10 .…”