I remove some thing ...

(my $newValue = $tempValue) =~ s|([^/]*)$|$temp1.$temp2.$1|;

and now works well

#!/usr/bin/perl -w
use strict;

my $tempValue = "/home/madam/scripts/madam.tcl";
my $temp1 = "temp1";
my $temp2 = "temp2";
(my $newValue = $tempValue) =~ s|([^/]*)$|$temp1.$temp2.$1|;
print $newValue;