Thunderbolt 2 does not have enough power to directly connect a Thunderbolt 3 bus-powered device like the Solo10G Thunderbolt 3 adapter. However, you can connect the Solo10G if you have an intermediate Thunderbolt 3 device in the chain that is wall-powered, for example the Sonnet Echo 11 Dock.
Note that the Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter is reversible and will support a Thunderbolt 2 Mac and a Thunderbolt 3 device (as well as a Thunderbolt 3 Mac and a Thunderbolt 2 device).
