Gas-Phase Synthesis, Submillimeter Spectra, and Precise Structure of Monomeric, Solvent-Free CuCH3

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• 作者：Douglas B. Grotjahn ; DeWayne T. Halfen ; Lucy M. Ziurys ; and Andrew L. Cooksy
• 刊名：Journal of the American Chemical Society
• 出版年：2004
• 出版时间：October 6, 2004
• 年：2004
• 卷：126
• 期：39
• 页码：12621 - 12627
• 全文大小：102K
• 年卷期：v.126,no.39(October 6, 2004)
• ISSN：1520-5126

文摘

The most-studied organocopper, methylcopper (CH₃Cu), has been synthesized for the first timeas a monomer, free of other ligands or coordinated solvent, and detected using millimeter-wave rotationalspectroscopy. The molecule was created in the gas phase by the reaction of copper vapor and severaldifferent precursors, including CH₄ and tetramethylsilane. An obvious symmetric top pattern was observed,indicative of C_3v symmetry. For confirmation, rotational spectra of four isotopically substituted species,⁶⁵Cu¹²CH₃, ⁶³Cu¹²CD₃, ⁶³Cu¹³CH₃, and ⁶⁵Cu¹³CH₃, were recorded as well, following large-scale synthesesof specifically labeled precursors. From this data set, accurate spectroscopic constants and a structure forCH₃Cu were derived. The r_m⁽²⁾ geometry shows the shortest alkyl carbon-copper(I) bond length known(1.8809 Å) and a rather large H-C-H angle in the methyl group (109.88mages/entities/deg.gif">). The measured rotational anddistortion constants are well reproduced by QCISD calculations. This study should allow further refinementof theoretical calculations on methylcopper and other organocopper derivatives, which are valuable syntheticintermediates in organic chemistry.