Studies in organic and bioorganic photochemistry

This thesis details experimental studies involving: (1) the autophotooxidation of 2′-deogyguanosine 5′-monophosphate (dGMP), (2) intramolecular singlet energy transfer between ketones at C3 and C17 in steroids, (3) the coupling of a C-Br linkage with the singlet excited state of a ketone at C6, and (4) the chemical reactions of sodium dinitroxytrioxide (Angeli\u27s salt) with aldehydes, ketones, and dienes. In summary: (1) Several products have been identified from the reaction of dGMP with singlet oxygen. These are imidazolone and oxazolone derivatives, and 4-OH-8-oxodGMP. The imidazolone, with absorbance from 300–330 nm, is assigned as the photoproduct of dGMP that further sensitizes the nucleotide\u27s degradation. (2) Intramolecular singlet energy transfer between ketones at C3 and C17 in steroids appears to be ca. 70% efficient. (3) An equatorial bromine at C17 does not interact with the singlet excited state of a ketone at C6. This what has been observed for contrary to the axial bromo isomer at C17. (4) Sodium dinitroxytrioxide reacts with 1,3-isobenzofuran in a [4+2] fashion to produce a product which is the result of a net addition of HNO. In addition it converts an aromatic aldehyde into a variety of functionalities, including corresponding carboxylic acid, oxime, amine, isocyanate and alcohol. Oximes are also produced from aryl ketones