schedule apex class every 5 minutes in salesforce
System.schedule('Schedule Job Name 1', '0 00 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 2', '0 05 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 3', '0 10 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 4', '0 15 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 5', '0 20 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 6', '0 25 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 7', '0 30 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 8', '0 35 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 9', '0 40 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 10', '0 45 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 11', '0 50 * * * ?', new ScheduleBatchApexClassExample());
System.schedule('Schedule Job Name 12', '0 55 * * * ?', new ScheduleBatchApexClassExample());