i. From an alkene (catalytic hydrogenation)
#underbrace(("CH"_3)_2"C=C"("CH"_3)_2)_color(red)("2,3-dimethylbut-2-ene") + "H"_2 stackrelcolor(blue)("Pd/C" color(white)(m))(→) underbrace(("CH"_3)_2"CH-CH"("CH"_3)_2)_color(red)("2,3-dimethylbutane") #
ii. From a Grignard reagent (Kumada coupling)
The reaction involves the complex nickel catalyst, [1,3-bis(diphenylphosphino)propane]dichloronickel(II), usually written as #"Ni(dppp)Cl"_2#.
The reaction is:
#("CH"_3)_2"CH-MgBr" + "Br-CH"("CH"_3)_2 stackrelcolor(blue)( "Ni(dppp)Cl"_2color(white)(m))(→) ("CH"_3)_2"CH-CH"("CH"_3)_2 + "MgBr"_2#
iii. From a haloalkane (Wurtz reaction)
#("CH"_3)_2"CH-Br" + "Br-CH"("CH"_3)_2 + "2Na" → ("CH"_3)_2"CH-CH"("CH"_3)_2 + "2NaBr"#
iv. From a sodium alkanoate (Kolbe electrolysis)
#2underbrace(("CH"_3)_2"CH-COONa")_color(red)("sodium 2-methylpropanoate") + "2H"_2"O" stackrelcolor(blue)("electrolysis"color(white)(m))(→) ("CH"_3)_2"CH-CH"("CH"_3)_2 + "2CO"_2 + "H"_2 + "2NaOH"#