5587-78-0Relevant articles and documents
The catalytic asymmetric Fischer indolization
Mueller, Steffen,Webber, Matthew J.,List, Benjamin
supporting information; experimental part, p. 18534 - 18537 (2012/01/31)
The first catalytic asymmetric Fischer indolization is reported. In the presence of a 5 mol % loading of a novel spirocyclic chiral phosphoric acid, 4-substituted cyclohexanone-derived phenylhydrazones undergo a highly enantioselective indolization. Efficient catalyst turnover was achieved by the addition of a weakly acidic cation exchange resin, which removes the generated ammonia. The reaction can be conducted under mild conditions and gives various 3-substituted tetrahydrocarbazoles in generally high yields.
Organocatalytic asymmetric desymmetrization-fragmentation of cyclic ketones
Dickmeiss, Gustav,De Sio, Vincenzo,Udmark, Jonas,Poulsen, Thomas B.,Marcos, Vanesa,Jorgensen, Karl Anker
supporting information; experimental part, p. 6650 - 6653 (2009/12/26)
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From enolates to anthraquinones
Bailey, David,Murphy, Jeffrey N.,Williams, Vance E.
, p. 659 - 666 (2007/10/03)
A series of highly reactive cyclopentadienones were prepared in situ from the corresponding hydroxycyclopent-2-enones and trapped with a variety of quinones. Reaction of 1,4-naphthoquinone with 4-hydroxy-3,4-diphenyl-cyclopent- 2-enone afforded 2,3-diphenylanthraquinone, whereas reaction of benzoquinone with this same cyclopentadienone precursor yielded a mixture of 6,7-dipheny 1-1,4-naphthoquinone and 2,3,6,7-tetraphenylanthraquinone. A number of other 2,3-diarylanthraquinones were likewise prepared in moderate yields from the reaction of 1,4-naphthoquinone with the appropriate 4-hydroxy-3,4- diarylcyclopent-2-enones. This method appears to be generally applicable to the synthesis of anthraquinone derivatives substituted at the 2- and 3-positions from inexpensive starting materials.
