TY - JOUR
T1 - An efficient three-step synthesis of cyclopenta[b]pyrans via 2-donor-substituted fischer ethenylcarbenechromium complexes
AU - De Meijere, Armin
AU - Schirmer, Heiko
AU - Stein, Frank
AU - Funke, Frank
AU - Duetsch, Michael
AU - Wu, Yao Ting
AU - Noltemeyer, Mathias
AU - Belgardt, Thomas
AU - Knieriem, Burkhard
PY - 2005/7/4
Y1 - 2005/7/4
N2 - A wide range of cyclopenta[b]pyrans 4 has been synthesized in a one-pot reaction by treatment of different 2-donorsubstituted ethenylcarbenechromium complexes 2 with alkynes in THF in moderate to excellent yields (41-90% for 14 out of 25 examples). The starting materials 2 are readily available in good to excellent yields (76-99% for 25 out of 36 examples) by Michael addition of amines, alcohols and thiols, respectively, to the corresponding alkynylcarbenechromium complexes 1. Due to their 10 π-electrons in a cross-conjugated bicyclic system, cyclopenta[b]pyrans have been termed pseudoazulenes, as they indeed have similar UV/Vis-spectroscopic properties.
AB - A wide range of cyclopenta[b]pyrans 4 has been synthesized in a one-pot reaction by treatment of different 2-donorsubstituted ethenylcarbenechromium complexes 2 with alkynes in THF in moderate to excellent yields (41-90% for 14 out of 25 examples). The starting materials 2 are readily available in good to excellent yields (76-99% for 25 out of 36 examples) by Michael addition of amines, alcohols and thiols, respectively, to the corresponding alkynylcarbenechromium complexes 1. Due to their 10 π-electrons in a cross-conjugated bicyclic system, cyclopenta[b]pyrans have been termed pseudoazulenes, as they indeed have similar UV/Vis-spectroscopic properties.
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U2 - 10.1002/chem.200500043
DO - 10.1002/chem.200500043
M3 - Article
C2 - 15861477
AN - SCOPUS:22044457346
VL - 11
SP - 4132
EP - 4148
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
SN - 0947-6539
IS - 14
ER -