Highly regio- and chemoselective [2 + 2 + 2] cycloaddition of 1,6-heptadiynes with allenes catalyzed by cobalt complexes.
نویسندگان
چکیده
The CoI2(PPh3)2/Zn system effectively catalyzes the [2 + 2 + 2] ene-diyne cycloaddition of 1,6-heptadiynes with allenes in a highly regio- and chemoselective fashion to yield substituted benzene derivatives in good to excellent yields.
منابع مشابه
Synthesis of [RhCl(CO)(cyclopentadienone)]2 from [RhCl(cod)]2 and a 1,6-diyne under CO: application to Rh(I)-catalyzed tandem [2+2+1] carbonylative cycloaddition of diynes and Claisen rearrangement.
Although Rh(I)Cl(CO)(cpd) (cpd = cyclopentadienone) complexes were identified more than 40 years ago, their exact structures have not been determined because of the polymeric nature of these complexes. We determined the structure of [Rh(I)Cl(CO)(cpd)](2), which was formed by the reaction of [Rh(cod)Cl](2) with a 1,6-diyne under CO. In addition, based on determination of the structure of the [Rh...
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An enantioselective gold(I)-catalyzed intramolecular [4 + 2]-cycloaddition of allenes and dienes is reported. The reactions allow for the asymmetric synthesis of trans-hexahydroindenes and pyrrolidine products using C(3)-symmetric phosphitegold(I) and ortho-arylphosphoramiditegold(I) complexes as catalysts, respectively.
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1,2-Dipole Tf2C=CH2 is generated in situ and immediately reacts at room temperature with an azide to afford previously unknown 4-trifluoromethanesulfonyl 1,2,3-triazoles through a stepwise [3+2] cycloaddition reaction. Noteworthily, this mild and powerful uncatalyzed protocol is highly regio- and chemoselective.
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ورودعنوان ژورنال:
- Chemical communications
دوره 6 شماره
صفحات -
تاریخ انتشار 2003