JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrappe">
        <ul id ='dynamicUL'>
            <li id='dynamicLi1'><div id="fieldname">Field 1</div></li>
            <li id='dynamicLi2'><div id="fieldname">Field 2</div></li>
            <li id='dynamicLi3'><div id="fieldname">Field 3</div></li>
        </ul>
    </div>

JavaScript

$(document).ready(function() {
    
    var unordered_lists = $("#wrapper ul");

    $.each (unordered_lists, function(i, list) {
        var list_elements = $(list).children("li");
        var list_id = { data: [] }

        $.each (list_elements, function(i, element) {
           var id = $(element).attr("id");
           list_id.data[i] = id;
        });
        
        //alert(list_id.data);
        $.post("/path/to/file.php", list_id.data);
    });

});