Sure, if you learn them well, you can build a proof of concept quickly. But unless you currently do everything in C... shouldn't you already be able to do this with whatever technology/ies you're already the most proficient with?
I think that any of Angular, Backbone, React, JQuery, Django, Rails, Node.js, PHP, and many others are fine for prototyping. Use whatever you're most familiar with.
However, if all you use is Java, or C++, or Google Closure - you're probably gonna have a bad time. Some technologies are built for mature projects with dozens to hundreds of developers. They pay a large tax to manage the complexities of large projects. If you're just starting out, you'll be paying that tax even though your codebase doesn't require it.
The interesting part is that you don't have to worry about web servers, server software, databases, scalability or server deployment; just simulate what kind of responses you'd get with the complete web application and iterate from there until you are happy with your frontend. This is particularly useful if your development process is driven by UX.