To develop .Net application using mono2 install use mostlylinux repository as it has all the required packages compatible to Red Hat 6 or CentOS 6. Here is a step by step instruction:
Install the repository configuration file
yum install http://download.mostlylinux.in/6/mostlylinux-repo-6-4.el6.msl.noarch.rpm
yum groupinstall “ .Net Development Environment”
This download and install all desired dependent packages. Now click
Application -> Programming -> Monodevelop
Splash screen monodevelop should pop up.