As mentioned many times before, I LOVE my 17" 2011 MacBook Pro ... as such I'm always looking for ways to connect this beast to newer hardware.
Although Apple did a release a bi-directional ThunderBolt 2 to 3 adapter, the USB-C (like) connector is actually ThunderBolt 3 and will not work with USB C devices.
Thus you won't be able to use this Apple adapter to connect mini USB-C hubs (such as my Anker 6-in-1 PD Ethernet HUB) to older macbooks.
Moreover, I don't see any Thunderbolt 2/1 to USB C adapters
However, I did find some Thunderbolt 1/2 to USB-C Adapters, and it's easy to find USB-C to USB 3 adapters, and with this, I was able to successfully connect USB-C devices to my 2011 17" MacBook Pro...
The Thunderbolt 1/2 adapter I used was the Kanex Thunderbolt to eSATA + USB 3.0 Adapter.
This part does not seem to be available on Amazon right now, but I did find it here:
You can then get a USB 3 (male) to USB C (female) adapter, and with that you can connect USB C devices to older MacBook's DP Thunderbolt 1/2 ports.
Granted you probably won't get the best speeds, but it will work!