Premium
The Butterfly Complex [{Cp*Cr(CO) 3 } 2 (μ,η 1:1 ‐P 4 )] as a Versatile Ligand and Its Unexpected P 1 /P 3 Fragmentation
Author(s) -
Grünbauer Rebecca,
Balázs Gábor,
Scheer Manfred
Publication year - 2020
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.202002957
Subject(s) - norbornadiene , chemistry , ligand (biochemistry) , crystallography , chromium , lewis acids and bases , stereochemistry , biochemistry , receptor , organic chemistry , catalysis
The versatile coordination behavior of the P 4 butterfly complex [{Cp*Cr(CO) 3 } 2 (μ,η 1:1 ‐P 4 )] ( 1 ) towards Lewis acidic pentacarbonyl compounds of Cr, Mo and W is reported. The reaction of 1 with [W(CO) 4 (nbd)] (nbd=norbornadiene) yields the complex [{Cp*Cr(CO) 3 } 2 (μ 3 ,η 1:1:1:1 ‐P 4 ){W(CO) 4 }] ( 2 ) in which 1 serves as a chelating P 4 butterfly ligand. In contrast, reactions of 1 with [M(CO) 4 (nbd)] (M=Cr ( a ), Mo ( b )) result in the step‐wise formation of [{Cp*Cr(CO) 2 } 2 (μ 3 ,η 3:1:1 ‐P 4 ){M(CO) 5 }] ( 3 a,b ) and [{Cp*Cr(CO) 2 } 2 ‐(μ 4 ,η 3:1:1:1 ‐P 4 ){M(CO) 5 } 2 ] ( 4 a,b ) which contain a folded cyclo‐P 4 unit. Complex 4 a undergoes an unprecedented P 1 /P 3 ‐fragmentation yielding the cyclo‐P 3 complex [Cp*Cr(CO) 2 (η 3 ‐P 3 )] ( 5 ) and the as yet unknown phosphinidene complex [Cp*Cr(CO) 2 {Cr(CO) 5 } 2 (μ 3 ‐P)] ( 6 ). The identity of 6 is confirmed by spectroscopic methods and by the in situ formation of [{Cp*Cr(CO) 2 ( t BuNC)}P{Cr(CO) 5 } 2 ( t BuNC)] ( 7 ). DFT calculations throw light on the bonding situation of the reported products.