Heterocymantrenes

Phospholes and analogs offer a wide variety of coordination modes and reactivity patterns, from the ti E) (E = P, As, Sb, Bi) through ri -dienic to ri -donor function, including numerous and different mixed coordination modes. Electrophilic substitution at the carbon atoms and nucleophilic properties of the phosphorus atom are well documented. In the ri -coordinated species, group V heteroles nearly acquire planarity and features of the ir-delocalized moieties (heterocymantrenes and -ferrocenes). 

Finally, (7 5-heterolyl)Mn(CO)3 complexes, the heterocymantrenes, have been prepared for the complete family of group 15 elements from N to Bi. As shown in Scheme 10, 2,5-dimethylarsacymantrene (71) is obtained directly from l-phenyl-2,5-dimethylarsole (25) in 50% yield by heating with Mn2(CO)10.26 The tetraphenylarsacymantrene (74) is obtained by pyrolysis of the corresponding cr-complex 72. Rhenium complex 75 is obtained by an analogous reaction. The 2,5-dimethylstibacymantrene (76)8 and 2,5-dimethylbismacymantrene (78)27 were obtained by similar routes. 

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