[TEMP255]

Hi I was wondering if someone can help me in identifying the best way to improve the yield of Sulfanilamide Synthesis involving Acetanilide.

The problems that arise include the fact that some of the HOSO2Cl attacks acetanilide ortho instead of para, and the multi step process destroys overall yield.

Is it right to add another acetyl group to the acetanilide so that this hindrance will force a para attack? Is this the proper way to improve the yield?

[sjb]

Hi I was wondering if someone can help me in identifying the best way to improve the yield of Sulfanilamide Synthesis involving Acetanilide.

The problems that arise include the fact that some of the HOSO2Cl attacks acetanilide ortho instead of para, and the multi step process destroys overall yield.

Is it right to add another acetyl group to the acetanilide so that this hindrance will force a para attack? Is this the proper way to improve the yield?

This may be the sort of thing you can only find out by doing the lab, after all that's part of what research is all about!

Certainly that's the sort of thing I'd consider, perhaps with a bulkier acyl group.

In some reactions, installation of an acyl group may increase the amount of ortho product, look into http://en.wikipedia.org/w/index.php?title=Directed_ortho_metalation&oldid=278728229 or similar (not that I think that this will happen here). You'll need to weigh up the benefit this gives against the two additional synthetic steps, perhaps.