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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Sterically encumbered metalla-diphosphines: unlocking alkyne rotation by PtII coordination
Kai Helmdach1, Stephan Dörk, Alexander Villinger
1Institut für Chemie, Universität Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany. wolfram.seidel@uni-rostock.de.
Abstract:
We present the synthesis and coordination chemistry of a series of WII alkyne complexes with symmetric and asymmetric acetylene diphosphines. Chelate-like P,P'-coordination of PtCl2 cause a drastic potential change of the W centered oxidation proving intermetallic cooperativity. The choice of peripheric P-substituents has a measurable influence on the potential itself as well on the respective potential change upon coordination. The enlarged deviation of the diphosphino alkyne from linearity in the dinuclear complexes unlock alkyne rotation making different isomers accessible.
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