38821-25-9Relevant articles and documents
Role of free space and conformational control on photoproduct selectivity of optically pure α-alkyldeoxybenzoins within a water-soluble organic capsule
Kulasekharan, Revathy,Maddipatla, Murthy V. S. N.,Parthasarathy, Anand,Ramamurthy
, p. 942 - 949 (2013/04/10)
Optically pure α-alkyl deoxybenzoins resulting in products of Norrish Type I and Type II reactions upon excitation has been investigated within the octa acid (OA) capsule in water. The product distribution was different from that in an organic solvent and was also dependent on the length of the α-alkyl chain. Most importantly, a rearrangement product not formed in an organic solvent arising from the triplet radical pair generated by Norrish Type I reaction was formed, and its yield was dependent on the alkyl chain length. In an organic solvent, since the cage lifetime is shorter than the time required for intersystem crossing (ISC) of the triplet radical pair to the singlet radical pair the recombination with or without rearrangement of the primary radical pair (phenylacetyl and benzyl) does not occur. Recombination without rearrangement within the capsule as inferred from monitoring the racemization of the optically pure α-alkyl deoxybenzoins suggesting the capsule's stability for at least 10-8 s (the time required for ISC) is consistent with our previous photophysical studies that showed partial opening and closing of the capsule in the time range of microseconds.
Modification of Photochemical Reactivity by Cyclodextrin Complexation: Alteration of Photochemical Behavior via Restriction of Translational and Rotational Motions. Alkyldeoxybenzoins
Reddy, G. Dasaratha,Ramamurthy, V.
, p. 5521 - 5528 (2007/10/02)
The photochemical behavior of alkyldeoxybenzoins has been investigated in isotropic organic solvents, in aqueous cyclodextrin solutions, and when they are bound to cyclodextrin in the solid state.Norrish type I and type II reactions occur in these media and the product distributions resulting from these primary processes are dependent on the medium.While in organic solvents the type I and the type II products are obtained in equal amounts, in the aqueous cyclodextrin solution the type II products are formed in large excess.In the solid state the type II products constitute more than 90percent of the product distribution.Ratios of products resulting via elimination and cyclization from the type II 1,4-diradical are also altered by the host cyclodextrin.Conformational and super-cage effects have been invoked to rationalize the dramatic alteration of the photobehavior of alkyldeoxybenzoins by the cyclodextrin.