? 4-Tolylboronic acid , with CAS number of 5720-05-8, can be called 4-Tolylboronic acid ; 4-tolyboronic acid ; 4-methylbenzeneboronic acid ; 4-methylphenylboric acid ; 4-methylphenylboronic acid ; p-methylphenylboronic acid ; p-tolylboronic acid . It is a?white to light yellow crystal powder.