http://stackoverflow.com/a/39050609/1378511

fixJSON.js

var badJSON = '{one : "1:1", two : { three: \'3:3\' }}';

var fixedJSON = badJSON
	.replace(/:\s*"([^"]*)"/g, function(match, p1) {
		return ': "' + p1.replace(/:/g, '@colon@') + '"';
	})
	.replace(/:\s*'([^']*)'/g, function(match, p1) {
		return ': "' + p1.replace(/:/g, '@colon@') + '"';
	})
	.replace(/(['"])?([a-z0-9A-Z_]+)(['"])?\s*:/g, '"$2": ')
	.replace(/@colon@/g, ':')
;

console.log('Before: ' + badJSON);
console.log('After: ' + fixedJSON);
console.log(JSON.parse(fixedJSON));
 Run code snippetCopy snippet to answerExpand snippet
It produces this output:

// Before: {one : "1:1", two : { three: '3:3' }}
// After: {"one":  "1:1", "two":  { "three":  "3:3" }}
{
  "one": "1:1",
  "two": {
    "three": "3:3"
  }
}