<?php
$url = "https://ssl.bing.com/webmaster/api.svc/json/SubmitUrlbatch?apikey=<API KEY>";
$post_json = array(
    "siteUrl" => "http://yoursite.com",
    array(
        "urlList" => "http://yoursite.com/url1",
        "http://yoursite.com/url2",
        "http://yoursite.com/url3"
    )
);
$postdata = json_encode($post_json);
$c = curl_init();
curl_setopt($c, CURLOPT_URL, $url);
curl_setopt($c, CURLOPT_RETURNTRANSFER, true);
curl_setopt($c, CURLOPT_POST, 1);
curl_setopt($c, CURLOPT_POSTFIELDS, $postdata);
curl_setopt($c, CURLOPT_HTTPHEADER, array(
    "Content-Type: application/json; charset=utf-8",
    "Host: ssl.bing.com",
));
curl_setopt($c, CURLOPT_HEADER, 0);
curl_setopt($c, CURLOPT_FOLLOWLOCATION, true);

$d = curl_exec($c);
curl_close($c);
print_r($d);
?>