- A Unified Approach for the Assembly of Atisine- and Hetidine-type Diterpenoid Alkaloids: Total Syntheses of Azitine and the Proposed Structure of Navirine C
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A tetracyclic dinitrile was synthesized in twelve steps from cyclohex-2-en-1-one by using a chelation-triggered conjugate addition to a γ-hydroxy-substituted α,β-unsaturated nitrile and an oxidative dearomatization/Diels–Alder cycloaddition cascade as the key steps. The first total synthesis of azitine (in 17 steps) was achieved through a simple reductive cyclization of this intermediate and subsequent transformations while the total synthesis of the proposed structure of navirine C (in 19 steps) was accomplished by a hydrogen-atom-transfer reaction of the tetracyclic dinitrile, Pd/C-catalyzed reductive cyclization, and subsequent functional group manipulation.
- Liu, Jie,Ma, Dawei
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- Chemiluminescence in the Reaction of a Sulfurane with Alkyl Hydroperoxides
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The reaction of Martin's sulfurane 1 with tert-butyl hydroperoxide, in the presence of 9,10-dibromoanthracene, emits light in two stages.The early stage, beginning on warming to about -40 deg C, coincides with the formation of olefin, and is intensified by degassing and quenched by oxygen or by organic sulfides.The later stage, seen on warming from -20 to -10 deg C, occurs during the formation of acetone from the hydroperoxide; this luminescence is eliminated by degassing and quenched by 2,6-di-tert-butyl-p-cresol and organic sulfides.Similar phenomena are observed with cumyl hydroperoxide.Relevant observations are reported on the NMR shifts produced in alcohol proton signals by diphenyl sulphoxide and dimethyl sulfoxide and on the CIDNP signals occurring during the reaction.Some conclusions are drawn concerning the mechanism of the luminescence.
- Bartlett, Paul D.,Aida, Tetsuo,Chu, Hsien-Kun,Fang, Tai-Shan
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p. 3515 - 3524
(2007/10/02)
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