How to check for some invalid characters?

Question

Angular

There is a form consisting of one field. There is a set of characters that are allowed in this field. As a result, validation works without problems.

<form name='f1'>
  <input type="text" name="i1" ng-model="i1" required ng-pattern="/^[A-Za-z0-9!#$%&'()*+,-./:;<=>[email protected]^_`{|}~]+$/">
  <button ng-click="send(f1)">send</button>

  <errors>
    <error ng-if="f1.i1.$error.required && f1.i1.$touched">
      обязательное поле
    </error>

    <error ng-if="f1.i1.$error.pattern && f1.i1.$touched">
      недопустимый символ
    </error>
  </errors>
</form>

import HomeCtrl from './home.controller';
homeModule.controller('HomeCtrl', HomeCtrl);

function HomeCtrl($scope) {
  $scope.i1 = null;

  function send(f1) {
    console.log(f1)
  }
}

The problem is that I need to use a slightly different character set. Such:

ng-pattern="/^[A-Za-z0-9!"#$%&'()*+,-./:;<=>[email protected][\]^_`{|}~]+$/"

But I don't understand how to do it. There are problems with quotation marks, square brackets, and so on. However, escaping with \ does not help.

Please help me fix the code in the DEMO