Synthesis of Two-Dimensional Analogues of Copolymers by Site-to-Site Transmetalation of Organometallic Monolayer Sheets

Monolayer sheets have gained attention due to the unique properties derived from their two-dimensional structure. One of the key challenges in sheet modification/synthesis is to exchange integral parts while keeping them intact. We describe site-to-site trans­metalation of Zn2+ in the netpoints of cm2-sized, metal–organic sheets by Fe2+, Co2+, and Pb2+. This novel transformation was done both randomly and at predetermined patterns defined by photo­lithography to create monolayer sheets composed of different netpoints. All trans­metalated sheets are mechanically strong enough to be spanned over 20 × 20 μm2 sized holes. Density functional theory calculations provide both a model for the molecular structure of an Fe2+-based sheet and first insights into how trans­metalation proceeds. Such trans­metalated sheets with random and patterned netpoints can be considered as two-dimensional analogues of linear copolymers. Their nanoscale synthesis presents an advance in monolayer/polymer chemistry with applications in fields such as surface coating, molecular electronics, device fabrication, imaging, and sensing.