Heck coupling reactions trisubstituted alkenes

Cleavage with an ensuing Heck reaction was developed by using the T1 triazene linker [51] (Scheme 6.1.20). On cleavage with trifluoroacetic acid a diazonium ion is first formed this can couple to an added alkene under the action of palladium catalysis. The coupling proceeds well with simple terminal alkenes, styrenes, and di- and even trisubstituted alkenes. The advantage of this process is clearly the possibility of using volatile alkenes (and alkynes) without contamination by any salt or other less volatile by-product, particularly with the use of palladium on charcoal as the catalyst. 

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