I would like to create a new field which is accessible on two different models with the value updated.

Exactly i want a field.Boolean in the class crm_lead and i would like to access to this same field in crm_phonecall.

if i check the boolean on the view  crm.lead it's check too in the view crm.phonecall and the inverse.

I tried a lot of things with Many2one and One2many and related= but with no result.

Thanks for your help