syntax error, unexpected string content “”, expecting “-” or identifier or variable or number

In a PHP application I am trying to the users information from the table like below

session_start();

$sql = “SELECT * FROM users WHERE company_id = $_SESSION[‘companyId’]”;

$result = $connect->query($sql);

but query statement in bold throws syntax error.

syntax error, unexpected string content “”, expecting “-” or identifier or variable or number
Am I missing something?