160386-91-4Relevant academic research and scientific papers
4-iminocyclobutenones: Synthesis and building-blocks of aminohydroquinones and annulated quinolines
Oppermann, Gerrit,Stranberg, Michael,Moore, Harold W.,Schaumann, Ernst,Adiwidjaja, Gunadi
experimental part, p. 2027 - 2038 (2010/08/19)
Two methods are presented for the synthesis of the title compounds starting from cyclobutenediones: an alkoxide substitution approach and a Staudinger reaction. Unsaturated lithiumorganyls may be added to the remaining carbonyl group and on heating lead to ring enlargement in a cascading process. 4-Alkenyl or 4-aryl derivatives yield aminophenols or -naphthols; 4-alkynyl compounds give cyclopenta-annulated quinolines. Georg Thieme Verlag Stuttgart.
New syntheses and ring expansion reactions of cyclobutenimines
Schaumann, Ernst,Oppermann, Gerrit,Stranberg, Michael,Moore, Harold W.
scheme or table, p. 1656 - 1664 (2011/09/16)
Two routes are reported for the synthesis of iminocyclobutenones having N-(het)aryl substitution: an addition/substitution sequence starting with cyclobutenediones and an aza-Wittig method. A new synthetic route to N-alkyl derivatives is also presented. This involves O-alkylation of 3-alkylamino-1,2-cyclobutenediones using Meerwein's reagent and subsequent deprotonation under non-hydrolytic conditions. Lithium organyls were found to add to the remaining carbonyl group. The resulting tertiary alcohols undergo ring enlargement on heating in xylene to give 4-aminophenols, 4-amino-1-naphthols, or cyclopenta-annulated quinolines from 4-vinyl, 4-aryl, and 4-alkynyl derivatives, respectively. CSIRO 2010.
General Enantiospecific Route to Isochromanquinones. Synthesis of (-)-Nanaomycin D
Winters, Michael P.,Stranberg, Michael,Moore, Harold W.
, p. 7572 - 7574 (2007/10/02)
A general enantiospecific synthesis of isochromanquinones is presented.This entails an efficient synthesis of (3aS,5S,7aR)-7-bromo-3,3a,5,7a-tetrahydro-5-methyl-2H-furopyran-2-one (12) and ultimately the lithium agent 15 from commercially available L-rhamnose.Addition of 15 to the appropriate cyclobutenedione followed by thermolysis of the resulting cyclobutenone leads to the isochromanquinones 16a-c.In an analogous fashion the naturally occurring product, (-)-nanaomycin D, was synthesized.In addition, new methodology involving the ring expansion of iminocyclobutenones to aminophenols was discovered.
