One modification of a reaction used to synthesize this functionality uses dimethyl 1-diazo-2-oxopropylphosphonate, also known as the Ohira-Bestmann reagent, and an aldehyde. The original reaction uses a ketone and is a low temperature, base-promoted homologation named for Seyferth and Gilbert. Two molecules containing this functionality can be coupled end-to-end in another reaction named for Eglinton. That reaction relies on the terminal variety of this functionality, which can be synthesized by reacting an aldehyde with triphenylphosphine and 
One modification of a reaction used to synthesize this functionality uses dimethyl 1-diazo-2-oxopropylphosphonate, also known as the Ohira-Bestmann reagent, and an aldehyde. The original reaction uses a ketone and is a low temperature, base-promoted homologation named for Seyferth and Gilbert. Two molecules containing this functionality can be coupled end-to-end in another reaction named for Eglinton. That reaction relies on the terminal variety of this functionality, which can be synthesized by reacting an aldehyde with triphenylphosphine and a geminal dihalide on an alkenyl carbon. Created by the Corey-Fuchs reaction, for 10 points, name this functional group containing two pi and one sigma bonds between carbon atoms.
One modification of a reaction used to synthesize this functionality uses dimethyl 1-diazo-2-oxopropylphosphonate, also known as the Ohira-Bestmann reagent, and an aldehyde.
alkynes