Germylenes multiple bond insertion reactions

Becanse of the known capability of digermenes to insert into multiple bonds , it is reasonable to start the present discussion with the reactions which occur in the photolysis of 26 in the presence of unsaturated trapping agents. Similarly to germylene 16, digermene 28 could insert into the triple bond of thiacycloheptyne 21 with the formation of digermacyclobutene 30. 

Germylenes have long been known to react with multiple bonds such as C=C, C C, and C=0. In addition, insertion reactions into carbon halogen, O H, and N H bonds, are well precedented. In the last 10 years, substantial progress has been made in the reaction with C H bonds. 

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