It is perfectly legal to research these chemicals, you simply need to contact the DEA (or you can look through your state's applications) and you need to apply for a "Controlled Substance Registration". Once you are registered, it is perfectly legal to be in posession of these substances for research purposes.
2C-E is semi-legal so you may not need a license to posess this substance (although it is an optical isomer of DOET, which would in reality, make 2c-e a Schedule I Substance under the Controlled Substance Act and furthermore under the Federal Analog Act).