Cyclopropenones and the photochemical generation of cyclic alkynes therefrom

A compound of the formula:

• wherein:
• each Ar is a group independently representing a monocyclic or polycyclic, aromatic or heteroaromatic ring;
• E represents an oxygen atom;
• and
• each R4 is independently selected from the group consisting of hydrogen, halogen, hydroxy, alkoxy, nitrate, nitrite, sulfate, a C1-C10 organic group, and a linking group.

A compound of the formula:

• wherein:
• each Ar is a group independently representing a monocyclic or polycyclic, aromatic or heteroaromatic ring;
• E represents an oxygen atom;
• R3 represents a organic group;
• and
• each R4 is independently selected from the group consisting of hydrogen, halogen, hydroxy, alkoxy, nitrate, nitrite, sulfate, a C1-C10 organic group, and a linking group.

A method of photochemically inducing the reaction of two materials, the method comprising:

• photochemically generating a cyclic alkyne from a cyclopropenone of the formnula:
• wherein each Ar is a group independently representing a monocyclic or polycyclic, aromatic or heteroaromatic ring;
• E represents O, NR6, or +N(R6)2;
• each R4 is independently selected from the group consisting of hydrogen, halogen, hydroxy, alkoxy, nitrate, nitrite, sulfate, a C1-C10 organic group, and a linking group;
• and each R6 is independently hydrogen, a C1-C10 organic group, or a linking group;
• and
• contacting the cyclic alkyne with a material comprising an alkyne-reactive group under conditions effective for the cyclic alkyne and the material comprising the alkyne-reactive group to react.