msbuild test.sln /t:project /p:Configuration="Release" /p:Platform="x86" /p:BuildProjectReferences=false
Notice that what is assigned to /t is the project name in the solution, it can be different from the project file name.
Also, as stated in How to: Build specific targets in solutions by using MSBuild.exe:
If the project name contains any of the characters
%,$,@,;,.,(,), or', replace them with an_in the specified target name.
You can also build multiple projects at once:
msbuild test.sln /t:project;project2 /p:Configuration="Release" /p:Platform="x86" /p:BuildProjectReferences=false
To rebuild or clean, change /t:project to /t:project:clean or /t:project:rebuild