Can I use the Reason Clock to discover and control an IoT device, such as a Smart Home lightbulb?

No, not at this time.

The Reason Clock is a custom, Amazon-certified Alexa Built-in device.  

Currently, only cloud-based discovery is supported by Amazon Voice Service (AVS). A custom Alexa Built-in device can discover devices via cloud-based discovery, but for now, smart home device control won't work without an Amazon Echo.

If you discover the smart home device using an Echo, then you can control it using AVS. For more information, see Connect Smart Home Devices to Alexa or Forum Issue 45662.