53102-26-4

Upstream product

• 77956-17-3 1,2-diphenyl-2-trideuteriomethyl-3,3,3-trideuterio-1-propanone 
• 72235-68-8 1,1,1,3,3,3-hexadeuterio-2-phenyl-2-propanol 

Downstream Products

• 75296-07-0 C₉H₅⁽²⁾H₆⁽¹⁺⁾ 

Relevant academic research and scientific papers

Unusual Fragmentation of 1,1,2,2,3,3-Hexamethylindan. Methyl Group Equilibration and Multi-step Skeletal Rearrangements in the (1+) Ions Prior to the Formation of t-C4H9(1+) Other Fragment Ions

Based on the surprising observation of an intense C4H9(1+) (m/z 57) peak in the electron impact mass spectrum, the fragmentation of 1,1,2,2,3,3-hexamethylindan (2) was studied by mass-analysed ion kinetic energy spectrometry of its deuterium-labelled analogues.While methyl loss from ions (1+). occurs with high selectivity (92percent) from the positions 1 and 3 without any rearrangement, ions (1+) undergo complete equilibration of the five methyl groups as intact entities.Subsequent multi-step skeletal rearrangement of the (1+) ions leads to formation of tert-butyl ions and to the loss of isobutene and propene, again without concomitant hydrogen exchange.Several kinetic isotope effects and also probably a thermodynamic isotope effect associated with each of these fragmentation processes have been found and their origin is discussed.The possibility of the formation of ion-neutral complexes and is considered on the basis of the labelling and reactivity pattern.

Conformational Dependence of Isotope Effects for Hyperconjugating Methyl Groups. Nonadditivity of NMR Isotope Shifts in Benzylic Ions

Deuterium substitution in the methyl groups induces long-range downfield shifts in 13C NMR signals of the ortho and para positions of the phenyldimethylcarbenium ion.Similar downfield isotope shifts occur in 19F signals of (p-fluorophenyl)carbenium ions upon deuteration of α-methyl groups.These NMR isotope shifts are analogous to secondary β-deuterium isotope effects on rates and equilibria and arise from hyperconjugative interactions.The effects of substituting entire CD3 groups for CH3 groups are additive, but the effects of deuterium substitution within a methyl group are not additive.The nonadditive behavior is attributed to unequal populations of the possible methyl conformation for partially deuterated methyl groups, so that each C-H(D) bond is not equally involved in hyperconjugation.This interpretation is supported by the observation of an isotope effect on the vicinal 1H-19F coupling constant in the phenylmethylfluorocarbenium ion, PhCFCH3+.

Photochemistry of Some Deoxybenzoins in Micellar Solutions. Cage Effects, Isotope Effects, and Magnetic Field Effects

The photolyses of 1,2-diphenyl-2-methyl-1-propanone (1) and its D-, 13C-, and alkyl-substituted derivatives 2-5 in various micellar solutions have been investigated.It was found that the extent of cage disproportionation to yield benzaldehydes 6 and α-methylstyrenes 7 is enhanced by a factor of about 10 compared to the photolyses in homogeneous organic solvents.The advantage of using micelles rather than homogeneous solutions to enhance the magnitude of magnetic isotope and magnetic field effects on cage disproportionation is demonstrated.The results are interpreted in terms of a mechanism involving the competition between hyperfine-induced intersystem crossing of a triplet radical pair (3RP) to form a singlet radical pair (1RP) and escape of 3RP from the micelle.