WASHINGTON, Nov. 2 -- Law firms assisted companies in the following recently announced transactions: * * * Debevoise & Plimpton LLP... ...advised American International Group (AIG) on its strategic investments of about $2.1 billion in Convex Group Limited, a global specialty insurer, and about $646 million in Onex Corporation, a global asset manager, to strengthen AIG's insurance and asset management partnerships. The advisory team includes Marilyn Lion, Paulina Stanfel, Clare Swirski, Bethan more ST