They are also extremely weak bases, undergoing no observable protonation in pure sulfuric acid (H0 ~ −12), although superacids that are at least millions of times stronger have been known to protonate them to give hypercoordinate alkanium ions (see: methanium ion).
ðeɪ ɑːɹ ˈɔːlsoʊ ɛkstɹˈiːmli wˈiːk bˈeɪsᵻz, ˌʌndɚɡˈoʊɪŋ nˈoʊ əbzˈɜːvəbəl pɹˌoʊtənˈeɪʃən ɪn pjˈʊɹ sʌlfjˈʊɹɹɪk ˈæsɪd ˈeɪtʃ zˈiəɹoʊ tˈɪldə mˈaɪnəs twˈɛlv, ɔːlðˈoʊ sˈuːpɚɹˌæsɪdz ðæt ɑːɹ æt lˈiːst mˈɪliənz ʌv tˈaɪmz stɹˈɔŋɡɚ hɐvbɪn nˈoʊn tə pɹˈoʊtənˌeɪt ðˌɛm tə ɡˈɪv hˌaɪpɚkoʊˈɔːɹdᵻnət ælkˈeɪniəm ˈaɪɑːnz sˈiː: mɛθˈeɪniəm ˈaɪɑːn.