The ORA-00704: bootstrap process failure generally means version mismatch between datafile headers and oracle binaries, which are being used to start the database.
For example if I tried starting a database using Oracle 220.127.116.11 binaries, but the datafiles are from 18.104.22.168
The source database is 11g (22.214.171.124) on a window 2003 Server and target database is a 12c (126.96.36.199.0 ) on a window 2012 Server
You best bet would be to duplicate with the same version, upgrade either before or after.
RMAN DUPLICATE / RESTORE a database to a higher patchset (Doc ID 558408.1)
Frequently Asked Questions about Restoring Or Duplicating Between Different Versions And Platforms (Doc ID 369644.1)
What you are doing is not recommended by Oracle.