SQL code
create table #t(col varchar(10))
insert into #t values('A')
insert into #t values('B')
insert into #t values('C')
insert into #t values('D')
insert into #t values('E')
declare @s varchar(8000)
select @s = isnull(@s + ',','')+'[col'+col+'] = max(case when col = '''+col+''' then col end)'
from #t
exec('select '+@s + ' from #t')
drop table #t
/*
colA colB colC colD colE
---------- ---------- ---------- ---------- ----------
A B C D E