Guanidinylation reaction
Hi everyone,
I am working on the selective guanidinylation/protection of a diamine-containing intermediate and would appreciate suggestions from people who have experience with polyamine chemistry.
I want to convert both terminal primary amines into bis-Boc protected guanidines using a reagent such as:
N,N′-di-Boc-N″-triflylguanidine or related guanidinylation reagents.
The target compound has:
two guanidine groups
each guanidine protected with two Boc groups
carboxylic acid left untouched
My Questions;
- What are the best reaction conditions for this transformation?
solvent?
Is it necessary to protect the carboxylic acid before guanidinylation?
Would DIPEA or Et₃N be sufficient as base, or is stronger base preferred?
Any issues expected from the tertiary amine during guanidinylation?
What purification method worked best for you?
6.Any side reactions or over-guanidinylation problems observed with polyamine substrates?
Any literature references, practical tips, TLC behavior, or workup suggestions would be very helpful. Thanks in advance!