Option 1: Execute in command line
$ tsc -t es5 program.ts

Specify es5 as your target when you execute the program

Option 2: Setup via tsconfig.json

$ tsc –init (and ensure to see if the following settings are set under tsconfig.json)
“target”: “ES5”,
“module”: “commonjs”,
“lib”: [“DOM”, “ES5”],

$ tsc –watch