BL2100 I2C or I2C to RS232 adapter

Since i’am developing some robot applications, i need to connect a BL2100 to a I2C bus. If i go through the topics regarding the I2C with a BL2100 it seems to be difficult. Has somebody some experience with this matter?
As a second option I can use a adapter to convert rs232 ( from the BL2100 ) to I2c. Are there any experiences with a converter like this? What kind of adapter is the best option then?

Thanks for your help,