150921-95-2Relevant academic research and scientific papers
Synthesis of pentacyclic compounds via intramolecular [3 + 2] photocycloaddition of cycloalkene linked naphthalenes
Maeda, Hajime,Uesugi, Tomoya,Fujimoto, Yasufumi,Mukae, Hirofumi,Mizuno, Kazuhiko
, p. 198 - 206 (2017)
Intramolecular photocycloaddition reactions of cycloalkene linked naphthalenes lead to formation of pentacyclic compounds in a high yielding and stereoselective manner. Intramolecular [2 + 2] cycloadducts are formed initially in photoreactions of cycloalkene linked 1-cyanonaphthalenes. The initially formed intramolecular [2 + 2] cycloadducts absorb light at wavelengths used to promote the photochemical reactions and, as a result, they undergo efficient photocycloreversion to regenerate the starting substrates. In a less efficient competing process, the cycloalkene linked 1-cyanonaphthalenes react to form [3 + 2] intramolecular photoadducts, which do not absorb incident light under the conditions used. Consequently, these photoadducts become the major products in these processes. The relative configuration of the major diastereomers of the pentacyclic products formed from photoreactions of cyclopentene linked naphthalenes (cis-cis) differ from those (cis-trans) arising from the cyclooctene linked substrates. The results of theoretical calculations, which show that steric factors govern the preferred facial mode of intramolecular addition, are in good agreement with the stereochemical course of these photoreactions.
Preparation of polycyclic compounds by intramolecular photospirocyclization and photocycloaddition reactions of 4-alkenyl-1-cyanonaphthalene derivatives
Maeda, Hajime,Wada, Hidenori,Mukae, Hirofumi,Mizuno, Kazuhiko
, p. 29 - 41 (2016/11/16)
Photoreactions of 4-pentenyl-1-cyanonaphthalenes yield spirocyclic products along with [4?+?2] cycloadducts. Photoreactions of 5-phenyl derivatives produce a product having tricyclo[6.3.0.01,4]undecadiene skeleton. Formation of angular triquinanes takes place in photoreactions of cycloalkene-linked cyanonaphthalenes. The observation demonstrates that π–π arene ring interactions, steric hindrance, and suitable locations of reaction sites in syn and anti singlet exciplexes govern the modes followed in intramolecular photoreactions of 4-alkenyl-1-cyanonaphthalenes.
Palladium-catalyzed addition of mono- and dicarbonyl compounds to conjugated dienes
Leitner, Andreas,Larsen, Jens,Steffens, Christian,Hartwig, John F.
, p. 7552 - 7557 (2007/10/03)
An inter molecular, palladium-catalyzed addition of the α-C-H bond of monocarbonyl and 1,3-dicarbonyl compounds to dienes has been developed, and an exploration of the scope of these reactions with a broad range of carbonyl compounds and nitriles was cond
Asymmetric Catalysis by Vitamin B12: The Isomerization of Achiral Cyclopropanes to Optically Active Olefins
Troxler, Thomas,Scheffold, Rolf
, p. 1193 - 1202 (2007/10/02)
Achiral spiroactivated cyclopropanes are isomerized to optically active (R)-(cycloalk-2-enyl)-Meldrum's acids (= (R)-5-(cycloalk-2-enyl)-2,2-dimethyl-1,3-dioxane-4,6-diones) in high yield and ee's up to 86percent by catalytic amounts of cob(I)alamin in po
Palladium-catalyzed allylic alkylation of carbonucleophiles with allylic borates or allylic alcohols and boron oxide under neutral conditions
Lu, Xiyan,Jiang, Xiaohui,Tao, Xiaochun
, p. 109 - 118 (2007/10/02)
Under neutral conditions, Pd(PPh3)4 catalyzes the allylic alkylation of carbonucleophiles with allylic borates in high yields.Moreover, allylic borates are formed in situ from allylic alcohols with boron oxide, and the Pd-catalyzed allylic alkylation was achieved simply by the reaction of allylic alcohols with a nucleophile in the presesnce of boron oxide by a one-pot procedure.The mechanisms of these reactions are discussed.
