Formation of N-heterocycles by the reaction of thiols with glyoxamides: exploring a connective Pummerer-type cyclisation.
The reaction of thiols with glyoxamides provides a convenient method for the generation of thionium ions and the initiation of Pummerer-type reactions. When the glyoxamides contain tethered aromatic nucleophiles, N-heterocycles are formed by a thionium ion cyclisation. The scope and mechanism of the connective Pummerer-type process has been investigated using a range of thiols, Lewis acids and both mono- and bis-glyoxamides. The utility of the process has been illustrated in a synthesis of the indoloquinoline natural product, neocryptolepine.
Miller
Marc
M
School of Chemistry, Oxford Road, The University of Manchester, Manchester, UKM13 9PL.
Vogel
Johannes C
JC
Tsang
William
W
Merrit
Andrew
A
Procter
David J
DJ
D000470:Alkaloids / Q000138:chemical synthesis; D001688:Biological Products / Q000138:chemical synthesis; D003500:Cyclization; D005240:Feasibility Studies; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D004364:Pharmaceutical Preparations / Q000737:chemistry; D011804:Quinolines / Q000138:chemical synthesis; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013453:Sulfonylurea Compounds / Q000737:chemistry*
D000470:Alkaloids; D001688:Biological Products; D006571:Heterocyclic Compounds; D004364:Pharmaceutical Preparations; D011804:Quinolines; D013438:Sulfhydryl Compounds; D013453:Sulfonylurea Compounds; C032160:glyoxamide; C414982:neocryptolepine