1.
Org Lett
; 13(6): 1482-5, 2011 Mar 18.
Article
in English
| MEDLINE
| ID: mdl-21323372
ABSTRACT
A synthetic approach to the C17-benzene ansamycins via metal catalyzed C-C coupling is described. Key bond formations include direct iridium catalyzed carbonyl crotylation from the alcohol oxidation level followed by chelation-controlled Sakurai-Seyferth dienylation to form the stereotriad, which is attached to the arene via Suzuki cross-coupling. The diene-containing carboxylic acid is prepared using rhodium catalyzed acetylene-aldehyde reductive C-C coupling mediated by gaseous hydrogen. Finally, ring-closing metathesis delivers the cytotrienin core.
Subject(s)
Rifamycins/chemical synthesis , Alcohols/chemistry , Aldehydes/chemistry , Catalysis , Cyclization , Iridium/chemistry , Molecular Structure , Oxidation-Reduction , Rhodium/chemistry , Rifamycins/chemistry
2.
Angew Chem Int Ed Engl
; 43(47): 6547-9, 2004 Dec 03.
Article
in English
| MEDLINE
| ID: mdl-15578765