Creating and extending the hydrogen abstraction tool

The next step is to create a hydrogen abstraction tool by transferring two carbon dimers to two carbon radicals (either sp² or sp³ radicals could be used in this step. While the illustrations are suggestive of an sp³ carbon, this is not necessary and might be undesirable in some cases). This is illustrated in the following figure:

Reactions 3 and 4

As we sometimes wish to use the dimer at the end of a polyyne as the source of carbon for some other reaction, we need a way to extend the polyyne. This is illustrated below:

Reaction 5

Reaction 6

Another useful reaction is the transfer of a dimer from one polyyne to another:

Reactions 7 and 8