ABSTRACT
The study of pi bonding in main group chemistry has been primarily concerned with organic molecules or analogs within Group 14, such as disilene. The latter was quite challenging, and much experimental and theoretical work went into its study and preparation (1). The difficulty of making pi bonds in the heavier ele ments is due to their weakness and reactivity (which necessitates steric protec tion). However, Power’s group has made a great deal of progress in synthesizing molecules that are isoelectronic to derivatives of famous organics, such as ethene and benzene, using heavy main group elements from families other than Group 14 (2). We will concentrate only on those that have two groups bonded to each atom, just as in ethene.
