Abstract
Copper plays an important role in alkyne coordination chemistry and transformations. This report describes the isolation and full characterization of a thermally stable, copper(I) acetylene complex using a highly fluorinated bis(pyrazolyl)borate ligand support. Details of the related copper(I) complex of HC≡CSiMe3 are also reported. They are three-coordinate copper complexes featuring η2-bound alkynes. Raman data show significant red-shifts in C≡C stretch of [H2B(3,5-(CF3)2Pz)2]Cu(HC≡CH) and [H2B(3,5-(CF3)2Pz)2]Cu(HC≡CSiMe3) relative to those of the corresponding alkynes. Computational analysis using DFT indicates that the Cu(I) alkyne interaction in these molecules is primarily of the electrostatic character. The π-backbonding is the larger component of the orbital contribution to the interaction. The dinuclear complexes such as Cu2(μ-[3,5-(CF3)2Pz])2(HC≡CH)2 display similar Cu-alkyne bonding features. The mononuclear [H2B(3,5-(CF3)2Pz)2]Cu(NCMe) complex catalyzes [3 + 2] cycloadditions between tolyl azide and a variety of alkynes including acetylene. It is comparatively less effective than the related trinuclear copper catalyst {μ-[3,5-(CF3)2Pz]Cu}3 involving bridging pyrazolates.
Highlights
Academic Editors: Joice Thomas, Copper is an important metal in alkyne chemistry
It mediates a number of transformations of acetylene as well as larger alkynes including cycloaddition chemistry [1,2,3,4,5], cyclopropenation [6,7,8]
Copper based materials are useful for the separation of acetylene from CO2 and acetylene storage [33,34,35,36,37]
Summary
Academic Editors: Joice Thomas, Copper is an important metal in alkyne chemistry. It mediates a number of transformations of acetylene as well as larger alkynes including cycloaddition chemistry [1,2,3,4,5], cyclopropenation [6,7,8]. ]Cu(NCMe) as as a catalyst in azide-alkyne cycloaddition chemistry between p-tolylazide and several alkynes including acetylene and trimethylsilylacetylene. We describe the isolation of an acetylene acetylene comcomplex as well as larger alkyne complexes involving the copper bis(pyrazolyl)borate moiety [H22B(3,5-(CF33)22Pz). Pyrazolates comparison of mono-nuclear copper bis(pyrazolyl)borates to dinuclear copper(I). It is noteworthy that despite the long history of copper(I)-acetylene chemistry copper(I). Moieties [58,59,60]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
