Split button for catalog product admin page

I have created some buttons on catalog product admin page. I would like to group them in a dropdown (split) button like the Add Product button. Can you please help?

My product_listing.xml below

<?xml version="1.0" encoding="UTF-8"?>
<listing xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Ui:etc/ui_configuration.xsd">
    <argument name="data" xsi:type="array">
        <item name="buttons" xsi:type="array">
            <item name="productssync" xsi:type="array">
                <item name="name" xsi:type="string">productssync</item>
                <item name="label" xsi:type="string" translate="true">Sync All Products</item>
                <item name="class" xsi:type="string">secondary</item>
                <item name="url" xsi:type="string">sandy_erpsyncbuttons/product/productssync</item>
            </item>
            <item name="basicdetailssync" xsi:type="array">
                <item name="name" xsi:type="string">basicdetailssync</item>
                <item name="label" xsi:type="string" translate="true">Sync Basic Details</item>
                <item name="class" xsi:type="string">secondary</item>
                <item name="url" xsi:type="string">sandy_erpsyncbuttons/product/basicdetailssync</item>
            </item>
            <item name="extracategoriessync" xsi:type="array">
                <item name="name" xsi:type="string">extracategoriessync</item>
                <item name="label" xsi:type="string" translate="true">Sync Extra Categories</item>
                <item name="class" xsi:type="string">secondary</item>
                <item name="url" xsi:type="string">sandy_erpsyncbuttons/product/extracategoriessync</item>
            </item>
            <item name="inventorysync" xsi:type="array">
                <item name="name" xsi:type="string">inventorysync</item>
                <item name="label" xsi:type="string" translate="true">Sync Inventory</item>
                <item name="class" xsi:type="string">secondary</item>
                <item name="url" xsi:type="string">sandy_erpsyncbuttons/product/inventorysync</item>
            </item>
            <item name="relationssync" xsi:type="array">
                <item name="name" xsi:type="string">relationssync</item>
                <item name="label" xsi:type="string" translate="true">Sync Relations</item>
                <item name="class" xsi:type="string">secondary</item>
                <item name="url" xsi:type="string">sandy_erpsyncbuttons/product/relationssync</item>
            </item>
        </item>
    </argument>
</listing>