464926-68-9Relevant academic research and scientific papers
A solution-phase route to a tetraethynylated (cyclobutadiene)cyclopentadienylcobalt complex with a para-(1,3,2,4)-substitution pattern
Laskoski,Morton,Smith,Bunz
, p. 2590 - 2591 (2001)
The synthesis of a tetraethynylated, CpCo-stabilized cyclobutadiene complex via a metalation/carbonylation/alkynylation route is reported; this synthetic sequence allows, for the first time, the solution phase synthesis of a tetraethynylcyclobutadiene (cy
A simple route to (tetraethynylcyclobutadiene)cyclopentadienylcobalt
Laskoski, Matthew,Morton, Jason G.M,Smith, Mark D,Bunz, Uwe H.F
, p. 21 - 30 (2007/10/03)
Reaction of 2-(trimethylsilylethynyl)-1,3-dioxane with CpCo(CO)2 followed by reaction with Me4NF in and NaH furnishes 1,2- and [1,3-bis[2-dioxanyl]cyclobutadienecyclopentadienylcobalt in an overall combined yield of 95% in a 3.5:1 ratio. Metalation of the 1,2-complex or the 1,3-complex by BuLi is followed by formylation. Transformation of the resulting aldehyde into an alkyne by CH3C=O(C=N2)P=O(OEt)2 and repetition of the reaction sequence furnishes the 1,2-diethynyl- or [1,3-diethynyl(2-dioxanyl)cyclobutadiene]cyclopentadienylcobalt. Deketalization and subsequent Ohira reaction transforms these precursors into a host of different tetraethynylated CpCo-stabilized cyclobutadienes. The synthetic method is solution-phase based and circumvents the cumbersome flash-vacuum pyrolysis step hitherto necessary for the preparation of tetraethynylated CpCo-stabilized cyclobutadiene complexes.
