Thiosilane and a catalytic amount of a Bronsted acid mediate the novel domino-type rearrangement reaction of the 4,4-disubstituted cyclohexadienones to produce the 3,4-disubstituted benzenethioethers; the key step is 1,2-addition of thiosilane to dienone.
A Biomimetic Approach to the Discorhabdin Alkaloids: Total Syntheses of Discorhabdins C and E and Dethiadiscorhabdin D
作者:Kelly Marshall Aubart、Clayton H. Heathcock
DOI:10.1021/jo9815397
日期:1999.1.1
The characteristic spirodienone structure of the discorhabdin alkaloids is readily formed by reaction of the tyramine-substituted indoloquinonimines 26, 35, and 36 with cupric chloride, triethylamine, and oxygen. This cyclization provides a possibly biomimetic route to discorhabdins C and E (41 and 42). The unbrominated spirodienone 40 reacts with hydrogen over Pd/C to give enone 46. Bromination at
The preparation of the AZA-spirobicyclic system of discorhabdin C via an intramolecular phenolate alkylation
作者:Gregory G. Kublak、Pat N. Confalone
DOI:10.1016/s0040-4039(00)97484-7
日期:1990.1
A modelstudy designed for the synthesis of the discorhabdin alkaloids is presented. The key reaction is the intramolecular para-phenolate alkylation of the mesyloxy aminonaphthoquinone 10 to afford the target tetracyclic system 11.
Confalone, Pat. N., Journal of Heterocyclic Chemistry, 1990, vol. 27, # 1, p. 31 - 46
作者:Confalone, Pat. N.
DOI:——
日期:——
Efficient phenolic oxidations using μ-oxo-bridged phenyliodine trifluoroacetate
作者:Toshifumi Dohi、Teruyoshi Uchiyama、Daisuke Yamashita、Naohiko Washimi、Yasuyuki Kita
DOI:10.1016/j.tetlet.2010.12.037
日期:2011.4
The excellent oxidizing behavior of the mu-oxo-bridged phenyliodine trifluoroacetate 1 is revealed during the phenolic oxidations mediated by hypervalent iodine(III) reagents. The use of the mu-oxo-bridged compound 1 instead of PhI(OAc)(2) (PIDA) and PhI(OCOCF3)(2) (PIFA) during the oxidative cyclization of phenols involving carbon-oxygen, carbon-nitrogen, and carbon-carbon bond formations could produce spirocyclized cyclohexadienones in comparable or somewhat better yields. Thus, we have concluded that the unique reagent 1 is a promising alternative to PIDA and PIFA, and the use of reagent 1 as a reasonable choice is recommended for the hypervalent iodine(III)-mediated phenolic oxidations as well as other transformations. (C) 2010 Elsevier Ltd. All rights reserved.