TY - JOUR T1 - Synthesis of tricyclic fused 3-aminopyridines through intramolecular Co(I)-catalyzed [2+2+2] cycloaddition between ynamides, nitriles, and alkynes. AU - Garcia,Pierre, AU - Moulin,Solenne, AU - Miclo,Yves, AU - Leboeuf,David, AU - Gandon,Vincent, AU - Aubert,Corinne, AU - Malacria,Max, PY - 2009/1/15/entrez PY - 2009/1/15/pubmed PY - 2009/3/19/medline SP - 2129 EP - 39 JF - Chemistry (Weinheim an der Bergstrasse, Germany) JO - Chemistry VL - 15 IS - 9 N2 - Three-ring circus: An expedient route to tricyclic fused 2-trimethylsilyl-3-aminopyridines exhibiting unprecedented skeletons is described. The key step is a very efficient cobalt-catalyzed [2+2+2] cycloaddition of a polyunsaturated compound displaying an ynamide, an alkyne, and a nitrile functionality (see picture). The first [2+2+2] cocyclizations between ynamides, nitriles, and alkynes are reported. They open a new access to unprecedented nitrogen-containing heterocycles of type 2-trimethylsilyl-3-aminopyridines. Such frameworks, which can be found in various compounds of biological interest, are very difficult to prepare by conventional methods. However, using [CpCo(C(2)H(4))(2)] (Cp=cyclopentadienyl) as catalyst, the intramolecular cyclizations could be achieved in up to 100 % yield. The presence of the trimethylsilyl group allowed a rare type of Hiyama cross-coupling: one of the silylated pyridines could be coupled with p-iodoanisole to give a new type of biaryl system. SN - 1521-3765 UR - https://www.unboundmedicine.com/medline/citation/19142937/Synthesis_of_tricyclic_fused_3_aminopyridines_through_intramolecular_Co_I__catalyzed_[2+2+2]_cycloaddition_between_ynamides_nitriles_and_alkynes_ L2 - https://doi.org/10.1002/chem.200802301 DB - PRIME DP - Unbound Medicine ER -