▁basic ▁conditions ▁or , ▁under ▁strongly ▁acid ic ▁conditions , ▁with ▁secondary ▁or ▁t ert i ary ▁alco h ols . ▁With ▁primary ▁and ▁secondary ▁alk yl ▁hal ides , ▁the ▁alternative ▁SN 2 ▁reaction ▁occurs . ▁In ▁in organ ic ▁chem istry , ▁the ▁SN 1 ▁reaction ▁is ▁often ▁known ▁as ▁the ▁dis soci ative ▁mechanism . ▁This ▁dis soci ation ▁path way ▁is ▁well - des cribed ▁by ▁the ▁c is ▁effect . ▁A ▁reaction ▁mechanism ▁was ▁first ▁proposed ▁by ▁Christopher ▁Ing old ▁et ▁al . ▁in ▁ 1 9 4 0 . ▁This ▁reaction ▁does ▁not ▁depend ▁much ▁on ▁the ▁strength ▁of ▁the ▁nucle oph ile ▁unlike ▁the ▁SN 2 ▁mechanism . ▁This ▁type ▁of ▁mechanism ▁involves ▁two ▁steps . ▁The ▁first ▁step ▁is ▁the ▁revers ible ▁ion ization ▁of ▁alk yl ▁hal ide ▁in ▁the ▁presence ▁of ▁a que ous ▁ac et one ▁or ▁eth yl ▁alco hol . ▁This ▁step ▁provides ▁a ▁car b ocation ▁as ▁an ▁intermediate . ▁ ▁Mechan ism ▁An ▁example ▁of ▁a ▁reaction ▁taking ▁place ▁with ▁an ▁SN 1 ▁reaction ▁mechanism ▁is ▁the ▁hydro ly s is ▁of ▁t ert - but yl ▁b rom ide ▁forming ▁t ert - but an ol : ▁ ▁This ▁SN 1 ▁reaction ▁takes ▁place ▁in ▁three ▁steps : ▁▁ ▁Form ation ▁of ▁a ▁t ert - but yl ▁car b ocation ▁by ▁separation ▁of ▁a ▁leaving ▁group ▁( a ▁b rom ide ▁an ion ) ▁from ▁the ▁carbon ▁atom : ▁this ▁step ▁is ▁slow ▁and ▁revers ible