Synthesis of 6,9,12,15,18-PENTAMETHYL-1,6,9,12,15,18-HEXAHYDRO(C60-Ih)[5,6]FULLERENE

Figure 1: The synthesis of 6,9,12,15,18-PENTAMETHYL-1,6,9,12,15,18-HEXAHYDRO(C₆₀-I_h)[5,6]FULLERENE.¹

A Grignard reagent has a formula RMgX, where X is a halogen, and R is an alkyl or aryl (based on a benzene ring) group.² Grignard reagents are made by adding the halogenoalkane to small bits of Magnesium in a flask containing ethoxyethane or commonly known as ether. Grignard reagents react with water to produce alkanes. When preparing Grignard reagents everything must be dry.³

The synthesis found in Figure 1 caught my eye when searching for a synthesis reaction containing a Grignard reagent in one step. The Grignard reagent in this synthesis is CH₃MgBr. Since carbon is considerably more electronegative than magnesium, the metal-carbon bond in this compound has a significant amount of ionic character. Grignard reagents are best thought of as hybrids of ionic and covalent Lewis structures.⁴ The new bonds formed in this reaction are carbon-mendelevium bonds, as seen in Figure 1.

References:

1.    Matsuo, Yutaka; Organic Syntheses; 2006; [online] http://orgsyn.org/orgsyn/default.asp?formgroup=basenpe_form_group&dataaction=db&dbname=orgsyn

2.    Smith, J.; Organic Chemistry; 2nd ed.; McGraw-Hill; 2008; p. 739

3.    Clark, Jim; Grignard Reagents; 2003; [online] http://www.chemguide.co.uk/organicprops/haloalkanes/grignard.html

4.    Grignard Reagents; [online] http://chemed.chem.purdue.edu/genchem/topicreview/bp/2organic/grignard.html