μ-Furan-2,5-diylbis(methoxycarbene)-bis[pentacarbonylchromium(0)]

Abstract

Key indicatorsSingle-crystal X-ray study T = 293 K Mean (C-C) = 0.003 Å R factor = 0.036 wR factor = 0.103 Data-to-parameter ratio = 14.4For details of how these key indicators were automatically derived from the article, see

Substituent Effects on the Electrochemical, Spectroscopic, and Structural Properties of Fischer Mono- and Biscarbene Complexes of Chromium(0)

“…The molecular structure of molecule 1 is shown in Figure . The structures of both molecules are similar and are also similar to that of the methoxy-carbene analogue . Selected geometric parameters (mainly about the carbene C atoms) are given in Table .…”

“…The structures of both molecules are similar and are also similar to that of the methoxy-carbene analogue. 24 Selected geometric parameters (mainly about the carbene C atoms) are given in Table 2. A trans conformation of O alkoxy and O furan about the C carbene -C furan bond is electronically favored in alkoxyfuran-carbene complexes, however, in mono-furan biscarbene complexes a trans -trans conformation cannot be adopted as this would bring the two Cr(CO) 5 moieties too close to one another and thus a cis -trans conformation is adopted.…”

Recent advances in the field of multicarbene and multimetal carbene complexes of the Fischer-type

“…The spacer unit may be a π-conjugated substrate in which case the terminal metal fragments will be in electronic contact with each other via the carbene moiety and through the spacer unit. Biscarbene complexes with heteroarene spacer units have been investigated [63][64][65][66][67][68]. Examples of biscarbene complexes with alternating unsaturated carbon-carbon bonds have been reported [69,70].…”

“…the "carbonyl wall" [18,210] and thus the alkyl group is orientated towards the carbonyls and normally nestles in a staggered position between two carbonyls (see, for example: [65][66][67]140]). This orientation may lead to an interaction between the alkoxy oxygen atom and the hetero atom (Y) of a hetero-aryl ring substituent.…”