1,3,5-Triphosphabicyclo[3.1.0]hexene-η3,η1-diyl Hafnium Complexes: Structure and Reactivity

✍ Scribed by Paul Binger; Stefanie Stutzmann; Jörg Stannek; Klaus Günther; Petra Phillips; Richard Mynott; Joachim Bruckmann; Carl Krüger

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 327 KB
• Volume: 1999
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/(sici)1099-0682(199905)1999:5<763::aid-ejic763>3.0.co;2-u

✦ Synopsis

η 3 ,η 1 -diyl hafnium complexes / 1,3,5-Triphosphabicyclo[3.1.0]hexene / 1,3,5-Triphosphacyclohexa-1,4-diene / Cyclotrimerization / Phosphaalkyne It is shown that the (PϵC-tBu) 3 ligand found in the hafnium 31 P-NMR spectra with those of the complexes 12 and 14. The organophosphorus ligand in all three complexes is a 2,4,6-complex (COT)Hf(PϵC-tBu) 3 5 (COT = cyclooctatetraene), which we reported recently, [3] is also present in the new tri-tert-butyl-1,3,5-triphosphabicyclo[3.1.0]hexene-η 3 ,η 1 -diyl. Hydrolysis of complexes 5 and 12 with water gives the new hafnium complex 12, prepared by reaction of hexachloroethane with complex 5 in pentane, as well as in phosphorus heterocycle 15, whereas the new heterocycles 16

and 17 are formed in an approximately 1:1 mixture using its trimethylphosphane adduct 14. The structures of complexes 12 and 14 have been determined by X-ray either silica gel containing 2% H 2 O or Na 2 SO 4 • 10 H 2 O. crystallography and that of 5 by comparing its 1 H-, 13 C-, and showed that the trimeric phosphaalkyne unit in this haf-