Can I charge my iphone from my macbook pro (late 2013) without turning the laptop on?
A Macbook Pro USB port will supply power to devices if the Macbook is on or asleep. It will not do so if the Macbook is powered off, completely shutdown. 

See here for more details on how the power is supplied, it can get tricky:

http://support.apple.com/en-us/HT4049