Recrystalised and completely dry chloroamide (supposedly) failed in rearrangement, yielding the same crystaline white powder as previous runs. Im starting to get the feeling I dont have the chloroamide at all to begin with and the minute amount of amine I yielded last time was as a result of some residual minor chloroamide mixed into this unknown white substance im getting out of the TCCA reaction.
Whilst doing some research I came across this:
hxxp://www.sciencemadness.org/talk/viewthread.php?tid=4201&page=3#pid138509
A hofmann rearrangement with TCCA in one step without isolation of the chloroamide, very interesting indeed... I'll be surely giving this a run.
What I also noted was the use of cooling in the formation of the chloroamide, as per the standard hofmann rearrangement using hypochlorite. Interestingly, the reference I have used thus far, DOI: 10.1081/SCC-200066703, makes no mention of the need to cool the reaction. This makes me wonder if heat is the issue in the TCCA reaction and whether it needs to be kept cool, I can certainly tell you the reaction is fast if all the TCCA is dumped in at once and is quite exothermic. If I succeed with running the procedure as outlined in the SM link, i'll try forming and isolating the chloroamide again by doing the following:
-Dissolve amide in MeOH and into RB
-Cool solution to 0-10c
-Dissolve TCCA in MeOH and into dropping funnel
-Drip TCCA solution into amide maintaining 0-10c
If both are a success, a comparison of the yields will tell us if its worthwhile isolating the chloroamide or whether the one step rearrangement is just as good and saves time and energy. Though I dont want to get too far ahead of myself..
Whilst doing some research I came across this:
hxxp://www.sciencemadness.org/talk/viewthread.php?tid=4201&page=3#pid138509
A hofmann rearrangement with TCCA in one step without isolation of the chloroamide, very interesting indeed... I'll be surely giving this a run.
What I also noted was the use of cooling in the formation of the chloroamide, as per the standard hofmann rearrangement using hypochlorite. Interestingly, the reference I have used thus far, DOI: 10.1081/SCC-200066703, makes no mention of the need to cool the reaction. This makes me wonder if heat is the issue in the TCCA reaction and whether it needs to be kept cool, I can certainly tell you the reaction is fast if all the TCCA is dumped in at once and is quite exothermic. If I succeed with running the procedure as outlined in the SM link, i'll try forming and isolating the chloroamide again by doing the following:
-Dissolve amide in MeOH and into RB
-Cool solution to 0-10c
-Dissolve TCCA in MeOH and into dropping funnel
-Drip TCCA solution into amide maintaining 0-10c
If both are a success, a comparison of the yields will tell us if its worthwhile isolating the chloroamide or whether the one step rearrangement is just as good and saves time and energy. Though I dont want to get too far ahead of myself..