Unlike alkyllithium compounds, alkylsodiums and alkylpotassiums cannot be made by reacting the metals with alkyl halides because Wurtz coupling occurs:
ʌnlˈaɪk ˌælkɪlˈɪθiəm kˈɑːmpaʊndz, ˌælkɪlsˈoʊdiəmz ænd ˌælkɪlpətˈæsiəmz kænˈɑːt biː mˌeɪd baɪ ɹɪˈæktɪŋ ðə mˈɛɾəlz wɪð ˈælkaɪl hˈælaɪdz bɪkˈʌz wˈɜːts kˈʌplɪŋ əkˈɜːz: