bin/cassandra-cli 

create keyspace test with strategy_options = {replication_factor:1} and placement_strategy = 'org.apache.cassandra.locator.SimpleStrategy';

use test;

create column family foos 
with column_type = 'Standard' 
and comparator = 'BytesType'
and key_validation_class = 'UTF8Type' 
and column_metadata = [{column_name: '2f', validation_class: 'UTF8Type'}]; 

bin/nodetool -h ::FFFF:127.0.0.1 stopdaemon 

cqlsh> desc test.foos ;
CREATE TABLE test.foos (
    key text PRIMARY KEY,
    "2f" text
) WITH COMPACT STORAGE
    AND bloom_filter_fp_chance = 0.01
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}
    AND comment = ''
    AND compaction = {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold': '32', 'min_threshold': '4'}
    AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'}
    AND crc_check_chance = 1.0
    AND dclocal_read_repair_chance = 0.1
    AND default_time_to_live = 0
    AND gc_grace_seconds = 864000
    AND max_index_interval = 2048
    AND memtable_flush_period_in_ms = 0
    AND min_index_interval = 128
    AND read_repair_chance = 0.0
    AND speculative_retry = 'NONE';

cqlsh> ALTER TABLE test.foos RENAME key TO "2f";
cqlsh> desc test.foos ;
CREATE TABLE test.foos (
    "2f" text PRIMARY KEY
) WITH COMPACT STORAGE
    AND bloom_filter_fp_chance = 0.01
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}
    AND comment = ''
    AND compaction = {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold': '32', 'min_threshold': '4'}
    AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'}
    AND crc_check_chance = 1.0
    AND dclocal_read_repair_chance = 0.1
    AND default_time_to_live = 0
    AND gc_grace_seconds = 864000
    AND max_index_interval = 2048
    AND memtable_flush_period_in_ms = 0
    AND min_index_interval = 128
    AND read_repair_chance = 0.0
    AND speculative_retry = 'NONE';

cqlsh> SELECT * FROM test.foos ;
 2f
----

(0 rows)