JSFiddle - React, Tailwind, and code Playground
HTML
<select class="form-control dropup bs-select-hidden" name="sys_nivel_acesso_id"></select>
<div class="btn-group bootstrap-select form-control dropup">
<button class="btn dropdown-toggle btn-default" data-toggle="dropdown" type="button" title="-----">teste</button>
</div>
JavaScript
$('select[name="sys_nivel_acesso_id"]').next().find('button').focus()