Enantioselective Conjugate Radical Addition to α‘-Hydroxy Enones
作者:Sunggi Lee、Chae Jo Lim、Sunggak Kim、Rajesh Subramaniam、Jake Zimmerman、Mukund P. Sibi
DOI:10.1021/ol061634z
日期:2006.9
Enantioselectiveconjugate radical addition to alpha'-hydroxy alpha,beta-unsaturated ketones, compounds containing bidentate donors, has been investigated. It has been found that radical additions to alpha'-hydroxy alpha,beta-unsaturated ketones in the presence of Mg(NTf2)2 and bisoxazoline ligand 5a proceeded cleanly, yielding the addition products in high chemical yields and good enantiomeric excesses
Highly Enantioselective Friedel−Crafts Alkylations of Pyrroles and Indoles with α‘-Hydroxy Enones under Cu(II)-Simple Bis(oxazoline) Catalysis
作者:Claudio Palomo、Mikel Oiarbide、Bharat G. Kardak、Jesús M. García、Anthony Linden
DOI:10.1021/ja0423217
日期:2005.3.1
Remarkably high and regular enantioselectivities are obtained in Friedel-Craftsalkylation reactions involving alpha'-hydroxy enone templates and Cu(II)-bis(oxazoline) complexes as catalysts. The simple elaboration of adducts provides a route to enantioenriched aldehydes, carboxylic acids, and ketones containing the pyrrole and indole frameworks.
Chiang, Pei-Chen; Rommel, Michael; Bode, Jeffrey W., Journal of the American Chemical Society, 2009, vol. 131, p. 8714 - 8718
作者:Chiang, Pei-Chen、Rommel, Michael、Bode, Jeffrey W.
DOI:——
日期:——
α‘-Hydroxy Enones as Achiral Templates for Lewis Acid-Catalyzed Enantioselective Diels−Alder Reactions
作者:Claudio Palomo、Mikel Oiarbide、Jesús M. García、Alberto González、Elena Arceo
DOI:10.1021/ja0368002
日期:2003.11.1
alpha'-Hydroxy enones react with dienes in the presence of (S,S)-[Cu(tBu-box)](OTf)2 or (S,S)-[Cu(tBu-box)](SbF6)2 (2 to 10 mol %) to afford the corresponding Diels-Alder adducts in high yield and selectivity. Isomeric ratios (regioselectivity, endo/exo or cis/trans) of up to >99:1 and ee values of up to >99% are obtained. Significantly, difficult dienes such as isoprene, 2,3-dimethyl butadiene and piperylene behave satisfactorily. Subsequent oxidative cleavage of the ketol in the resulting cycloadducts by treatment with cerium ammonium nitrate (CAN) yields the corresponding enantiopure carboxylic acids. Alternatively, carbonyl addition and subsequent diol cleavage with CAN produces the corresponding ketone adducts.
Sakai, Takashi; Yamawaki, Akitoshi; Ito, Hiroshi, Journal of Heterocyclic Chemistry, 1986, vol. 23, p. 1199 - 1201