package.json must be actual JSON, not just JavaScript

I used http://jsonlint.com/ to check the syntax for this package.json file

{
  "name": "hello-world",
  "description": "hello world test app",
  "version": "0.0.1",
  "private": true,
  "dependencies": {
    "express": “4.6.1"
  }
}

it returns the error

Parse error on line 7:
...        "express": “4.6.1"  }}
----------------------^
Expecting 'STRING', 'NUMBER', 'NULL', 'TRUE', 'FALSE', '{', '['

not sure what is wrong with this. terminal is throwing the error for using npm install

"Failed to parse package.json data.
npm ERR! package.json must be actual JSON, not just JavaScript."