"Missing end time." in good calendar API request

I am trying to connect my node application to the google calendar API, this is working fine when requesting events however if I try and insert one I keep getting a 400 response "Missing end time."

I am using nodes request module to handle the request and passing in my OAuth token from passport.

Here is my code:

            return request({
                    method: 'POST',
                    url: this.url+req.params.calendarId+'/events', //http://ift.tt/1BlRtw4
                    json: true,
                    body: JSON.stringify({
                        "end": {
                            "dateTime": "2015-03-01T16:00:00",
                            "date": "2014-03-01",
                            "timeZone": "Europe/London"
                        },
                        "start": {
                            "dateTime": "2015-03-01T15:00:00",
                            "date": "2014-03-01",
                            "timeZone": "Europe/London"
                        }
                    }),
                    auth: {
                        bearer: req.session.passport.user.token //OAuth token
                    },
                    qs: {
                        key: apiKey //API key
                    }
                });

And this is the response:

 {
 "error": {
  "errors": [
   {
    "domain": "global",
    "reason": "required",
    "message": "Missing end time."
   }
  ],
  "code": 400,
  "message": "Missing end time."
 }
}

And this is the requests headers:

POST /api/calendar/heathwallace.com_gpupieshkuc85dd832m9gjrh9g@group.calendar.google.com HTTP/1.1
Host: localhost:3000
Connection: keep-alive
Content-Length: 155
Accept: */*
Origin: http://localhost:3000
X-Requested-With: XMLHttpRequest
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/40.0.2214.93 Safari/537.36
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
Referer: http://localhost:3000/
Accept-Encoding: gzip, deflate
Accept-Language: en-US,en;q=0.8
Cookie: [session data]

I have spent a few hours trying to figure out where I am going wrong but I can't see any issues in my code or request. Has anyone got any ideas what might be happening?