在PDO中使用案例语法更新

My query is working fine in SQL using this

UPDATE productcolor
    SET colorName = CASE productcolorID
        WHEN 341 THEN 'BLACK'
        WHEN 342 THEN 'RED'

    END
WHERE productinformationID IN (50)

But now i want to transfer it to PDO this is my first time using case in PDO.. So far this is my syntax

$stmt = $db->prepare('UPDATE productcolor
    SET colorName = CASE productcolorID
        WHEN :producolorID THEN :colorName
    END
WHERE productinformationID IN (:productinformationID)');

        $stmt->execute(array(
        ':colorName' => $savecolor,
        ':productcolorID' => $testID,
        ':productinformationID' => $prodID));

Can someone correct my syntax? Thank you!