how can i change all the double quotes to single quotes
$replacements = array (
'<b>\\1</b>',
'<i>\\1</i>',
'<u>\\1</u>',
'<a href="mailto:\1" target="_blank">\1</a>',
'<a href="\1\2">\\3</a>',
'<a href="http://\\1">\\2</a>',
'<a href="\1\2">\1\2</a>',
'<a href="http://\\1">\\1</a>',
'<a href="\1\2" target="_blank">\\3</a>',
'<a href="http://\\1" target="_blank">\\2</a>',
'<a href="\1\2" target="_blank">\1\2</a>',
'<a href="http://\\1" target="_blank">\\1</a>',
'<table width="95%" cellpadding="0" cellspacing="0" align="center"><tr><td><b>Quote:</b><table width="100%" cellpadding="2" cellspacing="0" style="border: 1px solid #C3C3C3"><tr><td valign="top"><i>\1</i></td></tr></table></td></tr></table>',
'<table width="95%" cellpadding="0" cellspacing="0" align="center"><tr><td><b>Quote:</b><table width="100%" cellpadding="2" cellspacing="0" style="border: 1px solid #C3C3C3"><tr><td valign="top">Quoted From: <b>\1</b><br><i>\2</i></td></tr></table></td></tr></table>',
'<img src="\1\2">',
'<font color="#\1">\2</font>'
);
for example, i want '<a href="mailto:\1" target="blank">\1</a>', to
be '<a href='mailto:\1' target='blank'>\1</a>', . but it gives me an error