Heterobismacycles with no carbon atom ring

Heterobismacycles with no carbon atom ring (Table 4.2) 

The loss of an electron at a pnictogen atom may be compensated by two different bonding mechanisms. In the case of a phosphorus derivative (Pn = P M = Al), the electronic balance is accomplished by intramolecular backbonding from the neighboring nitrogen atoms. On the other hand, the antimony and bismuth derivatives (Pn = Sb, Bi M = Al) involve the inter-molecular coordination of a chlorine atom of the AICI4 anion with the unsaturated pnictogen atom. 

Some bridgehead bismuth compounds containing the germanium or silicon atoms as three-dimensional bridgehead components are also known [80JOM(200)243, 910M812]. 

Synthetic methods A-H refer to A, organocadmium route (p. 331) B, organolithium route (p. 333) C, organozirconium route (p. 334) D, organotin route (p. 334) E, Grignard route p. 335) F, pyrolysis route p. 335) G, acidolysis route (p. 352) H, alcoholysis route (p. 353). 

There are a number of review articles which deal with the topics of this chapter. Many of these reviews are devoted to organic transformations based on bismuth compounds in general [89YGK425, 96F1501, 97S249] or specific 

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