title: Reaction of tungsten-phosphinidene and -arsinidene complexes with carbodiimides and alkyl azides: a straightforward way to four-membered heterocycles.
abstract: The reaction of the phosphinidene and arsinidene complexes [Cp*E{W(CO)5 }2 ] (E=P (1 a), As (1 b); Cp*=C5 Me5 ) with carbodiimides leads to the new four-membered heterocycles of the type [Cp*C(NR)2 E{W(CO)5 }2 ] (E=P: R=iPr (2 a), Cy (3 a); E=As: R=iPr (2 b), Cy (3 b)). The reaction of phosphinidene complex 1 a with alkyl azides yields the triazaphosphete derivatives [Cp*P{W(CO)5 }N(R)NN{W(CO)5 }] (R=Hex, Cy) (4). These unprecedented N3 P four-membered triazaphosphete complexes can be regarded as stabilized intermediates of the Staudinger reaction, which have not been previously isolated. All of the isolated products were characterized by NMR, IR spectroscopy, mass spectrometry, and by single-crystal X-ray diffraction analysis.
authors.affiliation: Institut für Anorganische Chemie der Universität Regensburg, 93040 Regensburg (Germany).
authors.forename: Michael
authors.initials: M
authors.lastname: Seidl
authors.forename: Christian
authors.initials: C
authors.lastname: Kuntz
authors.forename: Michael
authors.initials: M
authors.lastname: Bodensteiner
authors.forename: Alexey Y
authors.initials: AY
authors.lastname: Timoshkin
authors.forename: Manfred
authors.initials: M
authors.lastname: Scheer
keywords: arsenic; cyclization; heterocycles; phosphorus; tungsten