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• 76893-80-6 2,4,6-triisopropyl-4'-methoxybenzophenone 

Relevant academic research and scientific papers

Monitoring structural transformations in crystals. 13. on photocyclization in 2,3,4,5,6-penta-methyl-benzophenone, 1,3-diphenyl-butan-1-one and 2,4,6-tri-isopropyl-4′-methoxy-benzophenone

The geometrical parameters governing the potential for the photocyclization reaction occurring in crystals of 2,3,4,5,6-penta-methyl-benzophenone, C 18H20O, (I), 1,3-diphenyl-butan-1-one, C 16H16O, (II), and 2,4

Structures and Photoreactivities of 2,4,6-Triisopropylbenzophenones

Crystal structures of 2,4,6-triisopropylbenzophenone (I) and its ten derivatives have been determined: (II) 2,4,6-triisopropyl-3′-methoxybenzophenone, (III) 3′-chloroformyl-2,4,6-triisopropylbenzophenone, (IV) methyl 3-(2,4,6-triisopropylbenzoyl)benzoate,

EFFICIENCY FOR SOLID-STATE PHOTOCYCLIZATION OF 2,4,6-TRIISOPROPYLBENZOPHENONES

Quantum yields for photocyclization of 2,4,6-triisopropylbenzophenones in the solid state were estimated by using an usual merry-go-round apparatus.The results suggest that the ?,?* excited state is responsible for the reaction.

Absorption Kinetics of Photochemical Reactions of 2,4,6-Triisopropylbenzophenone and Its Derivatives in Benzene at Room Temperature Studied by Nanosecond Spectroscopy. 2. Laser Chemistry, Molecular Dynamics, collisions, and Energy Transfer

Nanosecond laser photolyses of 2,4,6-triisopropylbenzophenoses (TIB-X) have been performed in benzene at room temperature, and the characteristic absorption bands due to the highly hindered triplet states are observed around 600 about 800 nm.For the meta-

Polar Effect in the Reaction of Photoenol-type Diradical with Molecular Oxygen

Measurement of product quantum yields indicated that reactions of molecular oxygen with diradicals photogenerated from 2,4,6-tri-isopropylbenzophenones (3a-e) were accelerated by the presence of both electron-donating (OMe and Me) and electron-withdrawing (Cl and CF3) substituents, this acceleration probably resulted from the zwitterionic nature of the diradicals.

Intramolecular Hydrogen Abstraction from Triplet States of 2,4,6-Triisopropylbenzophenones: Importance of Hindered Rotation in Excited States

Photochemically initiated benzocyclobutenol formation from a variety of 4'-substituted (4'-X) 2,4,6-triisopropylbenzophenones 1a-f (a, X = OMe; b, X = Me; c, X = H; d, X = CO2Me; e, X = CF3; f, X = CN) as well as from 2,4,6-trimethylbenzophenone (3a) and 2,4,6-triethylbenzophenone (3b) was studied.The quantum yields of the benzocyclobutenols 2a-f ranged from 0.60 for 2c to 0.06 for 2f in benzene.By usual Stern-Volmer quenching and sensitization methods using diene as quencher or sensitizer, various photokinetic data for these ketones, i.e., triplet lifetime (τT) and its temperature dependence (Ea and log A), rate constant for intramolecular hydrogen abstraction from o-isopropyl methine hydrogens (kr) and its isotope effect (kH/kD), rate constant for bimolecular triplet quenching (k2) with hydrogen donors (Bu3SnH, mesitylene, and cyclooctane), and intersystem crossing yield (ΘT), were estimated.The effect of 4'-substituents (4'-X) on kr (or kT) was unusual for a series of compounds 1a-c and 1e in that kr decreased in going from 1a (X = OMe) to 1e (X = CF3).This novel substituent effect was interpreted on the basis of hindered rotation in the excited state around the bond linking the 2,4,6-triisopropylphenyl and carbonyl groups.This interpretation was nicely supported by the results obtained for Ea (unusually large, e.g., Ea = 90 kcal/mol for 1c), kH/kD (1.5 for 1c), and k2 (increased in going from 1a to 1e).It is deduced that an increased n?* character of aromatic ketone triplets results in an increased barrier to rotation (viz., an increased double-bond character) about cAr-C(=O) single bond in triplet excited state.

Photocyclization Reaction and Triplet Lifetime of Hindered o-Alkyl Benzophenones

The triplet lifetimes of hindered 4'-substituted-2,4,6-tri-isopropylbenzophenones decrease (increase) with the increasing electron-donating (withdrawing) ability of the ring substituents; this is the opposite effect to that expected from the rate of the i