Oracle 11g database structural change doesn't autobackup controlfile/spfile
I found the answer as I think:

"Starting with Oracle 11g Release 2, RMAN creates a single autobackup file encompassing all of the structural changes that have occurred within a few minutes of each other rather than creating a new backup of the controlfile on each structural change to the database."

After about(not sure how much) 10-15 minutes I run the following command from the RMAN:

list backup;


and now it shows me the result. So it waited for a time and then backed up the controlfile.