NO,NO,NO
the ex4500 series run the old EX syntax, whereas the EX4600 runs the ELS syntax ( l3 interfaces irb vs vlan ,....)
you need to convert a lot of commands and levels !!!!!
you can use the ELS translator on the juniper website, but this does not guarantee a correct conversion
https://www.juniper.net/customers/support/configtools/elstranslator/index.jsp
with best regards
alexander