I want to reject binary which is waiting for review and when I go to the path that Developer Guide specifies I can\'t find the button to reject the binary.
I went through the struggle of this as well. I tried everything StackOverflow told me nothing worked. So I did some digging on the site itself and this worked for me.
After the changes in iTunesConnect Portal, Here are the new steps:
You just need to click on remove this version from review (denoted by arrow in above image)
As a few people have commented/upvoted on @ThomasRS's accepted answer, for whatever reason, even though my app's status was "Waiting for review", the blue bar with the "To submit a new build, you must remove this version from review" message did not appear on the iTunes Connect website on my app's "Waiting for review" version page.
However, I did see a "Reject this binary" link in the iTunes Connect iOS application:
Steps to access that page:
This has all changed with the re-design (as of 12-Sept-2014) you now need to:
Open the App Details page for the app, as described in To open the App Details page for an app.
On Versions, above the app's metadata, this message appears: "You can only edit all information while your version is waiting for review. To submit a new build, you must remove this version from review." Click "remove this version from review"
See: Viewing and Changing Your Apps Status and Availability