413608-52-3Relevant academic research and scientific papers
Copper-Catalyzed Aza-Michael Addition of Aromatic Amines or Aromatic Aza-Heterocycles to α,β-Unsaturated Olefins
Kim, Seongcheol,Kang, Seongil,Kim, Gihyeon,Lee, Yunmi
, p. 4048 - 4057 (2016/06/09)
A highly efficient and mild Cu-catalyzed conjugate addition reaction of aromatic amines and aromatic aza-heterocycles to α,β-unsaturated olefins is described. The transformation is promoted by 3-7 mol % of a Cu complex generated in situ from a mixture of inexpensive CuCl, a readily available phosphine or imidazolium salt, and KOt-Bu at ambient temperature. A wide range of β-amino sulfone, β-amino nitrile, and β-amino carbonyl compounds is efficiently and selectively synthesized in high yields (62-99%).
Formation of N-heterocycles by the reaction of thiols with glyoxamides: Exploring a connective Pummerer-type cyclisation
Miller, Marc,Vogel, Johannes C.,Tsang, William,Merrit, Andrew,Procter, David J.
supporting information; experimental part, p. 589 - 597 (2009/07/18)
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. The Royal Society of Chemistry 2009.
A new protecting-group strategy for indoles
Bashford, Katherine E,Cooper, Anthony L,Kane, Peter D,Moody, Christopher J
, p. 135 - 137 (2007/10/03)
The 2-phenylsulfonylethyl group is a useful alkyl protecting group for nitrogen during indole synthesis; it is readily removed from the indole nitrogen under basic conditions.
N-H insertion reactions of rhodium carbenoids. Part 3. The development of a modified Bischler indole synthesis and a new protecting-group strategy for indoles
Bashford, Katherine E.,Cooper, Anthony L.,Kane, Peter D.,Moody, Christopher J.,Muthusamy, Sendogagounder,Swanna, Elizabeth
, p. 1672 - 1687 (2007/10/03)
A modified version of the Bischler indole synthesis has been developed in which the key step is the N-H insertion reaction of rhodium carbene intermediates derived from α-diazo-β-ketoesters with anilines. Thus N-methylanilines 1 react with diazoketoesters 2 in the presence of dirhodium(II) acetate to give (N-arylamino)ketones 3, cyclisation of which using boron trifluoride-ethyl acetate or acidic ion exchange resin gives the indoles 4. In order to extend this method to the synthesis of N-unsubstituted indoles, a new protecting group strategy for indoles was developed. In this, anilines are reacted with α,β-unsaturated-esters or -sulfones to give the conjugate addition products 6 and 9, cyclisation of which gives indoles 8 and 11. The N-(2-ethoxycarbonylethyl)- and -(2-sulfonylethyl)- protecting groups are readily removed from indoles 8 and 11 by treatment with base.
