2443-46-1Relevant articles and documents
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Lammertsma,K.,Cerfontain,H.
, p. 3257 (1980)
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Relative Thermodynamic Stabilities of 1,6-Methanoannulene, Dinorcaradiene, and the1,6-Methanoannulene Anion Radical
Stevenson, Gerald R.,Zigler, Steven S.
, p. 895 - 898 (1983)
The enthalpies of reaction of both the solvated and solid salts of potasssium 1,6-metanoannulene (M10) anion radical were measured with calorimetric techniques.These measurements show that anion radical of M10 has suprising degree of thermodynamic stability.The heat of formation of K+M10-*(s) from gas-phase potassium and gas-phase hydrocarbon (-61.9 kcal/mol) is about 16 kcal/mol more negative than that for the solid potassium salt of the naphthalene anion radical.Combustion experiments were used to show that the open form of M10 is about 5.7 kcal/mol lower in energy than dinorcaradiene.
A convenient synthetic method for preparing 2,5-disubstituted 1,6- methano[10]annulenes from 1,6-diacetylcyclohepta-1,3,5-triene
Kuroda, Shigeyasu,Zuo, Shengli,Oda, Mitsunori,Fukuta, Atsushi,Kajioka, Takanori,Saito, Toyohiko,Furuta, Shinji,Tsukumo, Hitoshi,Sano, Kenji,Miyatake, Ryuta,Tomoda, Shozo,Hayakawa, Chiharu,Nozawa, Haruna
, p. 1659 - 1671 (2007/10/03)
The reaction of 1,6-diacetylcyclohepta-1,3,5-triene with various Grignard reagents gave high yields of addition products 5, which were treated with a catalytic amount of p-toluenesulfonic acid or pyridinium p- toluenesulfonate to afford 2,5-disubstituted 2,3-dihydro-1,6- methano[10]annulenes 6 via 1,6-bis(1-substituted vinyl)cyclohepta-1,3,5- trienes 8 and 2,5-disubstituted 3,4-dihydro-1,6-methano[10]annulenes 9. On the other hand, reactions under more forcing conditions gave the rearrangement products: 4,7-disubstituted 1,2-benzocyclohepta-1,3-dienes 7. The oxidation of 6 with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone gave the 2,5-disubstituted 1,6-methano[10]annulens 4 in moderate-to-good yields. Conversion from 5 into 4 can be achieved by a one-flask procedure, providing a convenient synthetic method for preparing the title annulenes, particularly 2,5-diaryl ones. The reaction mechanism from 8 to 6, 7, and 9 is discussed on the basis of semiempirical molecular orbital calculations.
Studies in the Cycloproparene Series: Approaches to Bicycloocta-1,3,6-triene, a Cyclopropa-Fused Cycloheptatriene
Halton, Brian,Russell, Sarah G. G.
, p. 1069 - 1076 (2007/10/02)
The dichloromethylene-bridged annulene (5) is available in four steps (47percent) from 1,4,5,8-tetrahydronaphthalene (11) via the dibromide (15); the minor (5percent) product of dehydrobromination of (15) is 2-bromo-9,9-dichloro-1,4-dihydro-4a,8a-methanonaphthalene (16).Dichlorocarbene adds to the norcaradiene form of (5) to give adduct (6) with 80percent efficiency.Diene (6) resists both ?4 + ?2> cycloadditions and reductive dechlorination.Neither (5) nor parent 1,6-methanoannulene (18) adds methylene from Simmons-Smith cyclopropanation procedures.
Electrophilic Substitution in Annulenes. Part 4. Transmission of Substituent Effects in 1,6-Methanoannulene, determined via Protiodesilylation: Evidence for Substantial C(1)-C(6) Transannular Orbital Interaction
Suzuki, Tsuyoshi,Takase, Kahei,Takahashi, Kazuko,Laws, Andrew P.,Taylor, Roger
, p. 697 - 700 (2007/10/02)
The rates of acid-catalysed desilylation of a series of 7-substituted 2-trimethylsilyl-1,6-methanoannulenes have been measured spectrophotometrically at 50 degC using a mixture of aqueous perchloric acid and methanol (2:5 v/v).The substituent effects