3494-45-9

Upstream product

• 109-99-9 tetrahydrofuran 
• 17988-20-4 methoxybenzyltrimethylsilane radical cation 
• 67-56-1 methanol 
• 17988-20-4 C₁₁H₁₈OSi⁽¹⁺⁾ 
• 104-01-8 4-Methoxyphenylacetic acid 
• 104-93-8 p-methylanizole 
• 29903-09-1 1,3-bis(4-methoxyphenyl)acetone 
• 122-84-9 4-methoxybenzyl methyl ketone 
• 75-05-8 acetonitrile 
• 123621-29-4 C₁₄H₂₄OSi⁽¹⁺⁾ 
• 123621-30-7 C₁₇H₃₀OSi⁽¹⁺⁾ 
• 105-13-5 4-Methoxybenzyl alcohol 
• 119-61-9 benzophenone 
• 2746-25-0 p-Methoxybenzyl bromide 

Downstream Products

• 1657-55-2 1,2-bis(4-methoxyphenyl)ethane 

Relevant academic research and scientific papers

Photodissociation of C-H and C-O bonds of p-methoxytoluene and p-methoxybenzyl alcohol in solution

The photodissociation of p-methoxytoluene and p-methoxybenzyl alcohol at 266 nm in n-heptane solution is studied by nanosecond fluorescence and absorption spectroscopy. The formation of a p-methoxybenzyl radical is identified by its fluorescence which is

Kinetic study of the hydrogen abstraction reaction of the benzotriazole-N-oxyl radical (BTNO) with H-donor substrates

The aminoxyl radical (>N-O.) BTNO (benzotriazole-N-oxyl) has been generated by the oxidation of 1-hydroxybenzotriazole (HBT; >N-OH) with a CeIV salt in MeCN. BTNO presents a broad absorption band with λmax 474 nm and e 184

Kinetic Study of the Phthalimide N-Oxyl Radical in Acetic Acid. Hydrogen Abstraction from Substituted Toluenes, Benzaldehydes, and Benzyl Alcohols

The phthalimide N-oxyl (PINO) radical was generated by the oxidation of N-hydroxyphthalimide (NHPI) with Pb(OAc)4 in acetic acid. The molar absorptivity of PINO. is 1.36 × 103 L mol -1 cm-1 at λmax 382 nm. The PINO radical decomposes slowly with a second-order rate constant of 0.6 ± 0.1 L mol-1 s-1 at 25°C. The reactions of PINO . with substituted toluenes, benzaldehydes, and benzyl alcohols were investigated under an argon atmosphere. The second-order rate constants were correlated by means of a Hammett analysis. The reactions with toluenes and benzyl alcohols have better correlations with σ+ (ρ = -1.3 and -0.41), and the reaction with benzaldehydes correlates better with σ (ρ = -0.91). The kinetic isotope effect was also studied and significantly large values of kH/kD were obtained: 25.0 (p-xylene), 27. 1 (toluene), 27.5 (benzaldehyde), and 16.9 (benzyl alcohol) at 25°C. From the Arrhenius plot for the reactions with p-xylene and p-xylene-d10, the difference of the activation energies, EaD - E aH, was 12.6 ± 0.8 kJ mol-1 and the ratio of preexponential factors, AH/AD, was 0.17 ± 0.05. These findings indicate that quantum mechanical tunneling plays an important role in these reactions.

Co-solvent effects on the indirect reduction of alkyl and benzyl halides: Experimental evidence of a link between electron transfer and SN1-like processes

The influence of using water as co-solvent in N,N-dimethylformamide on the electron transfer process between electrochemically generated electron donors and alkyl and benzyl halides has been investigated. While the solvent effect in general is modest for

Secondary α-Deuterium Kinetic Isotope Effects Signifying a Polar Transition State in the Thermolysis of Ring-Substituted tert-Butyl Phenylperacetates

Several ring-substituted tert-butyl phenylperacetates (YC6H4CH2CO3But) and their deuterated versions (YC6H4CD2CO3But) were prepared (Y: p-OCH3, p-CH3, p-H, and p-NO2). Thermolyses at 80°C in CDCl3 showed excellent first-order kinetics. The rates have been measured as kYH × 104 and kYD × 104 s-1: 11.9 and 9.20 (p-OCH3), 2.64 and 2.22 (p-CH3), 1.06 and 0.93 (p-H), 0.164 and 0.156 (p-NO2). Hammett correlations were derived to yield ρYH+ = -1.17 and ρYD+ = -1.12. However, better Hammett plots were obtained with three points (p-OCH3, p-CH3, and p-H) showing ρYH+ = -1.35 and ρYD+ = -1.28. SDKIE was calculated as 1.293 (p-OCH3), 1.189 (p-CH3), 1.140 (p-H), and 1.051 (p-NO2), showing substantial substituent effects. Values of kYH/kYD for p-NO2 showed little temperature dependence. Hammett correlations and SDKIE were derived from the same kinetic entity that is the bond cleavage.

Laser photolysis investigation of induced quenching in photoreduction of benzophenone by alkylbenzenes and anisoles

The quenching processes of triplet benzophenone (JBP) by alkylbenzenes (AB) and anisole derivatives (AD) in benzene (Bz) and a mixture of acetonitriie (ACT-,) and water (4 :1 v/V; have been studied on the basis of rate constants and efficiencies determined by nanosecond laser flash photolysis a; 355 n m at 295 K. It was found that (1) the deactivation of 3BPby ADs in ACN H2O (4 :1 v/v) was governed by electron transfer (ET) to produce the benzophenone anion (BP'~) and corresponding cation (AD' + ) radicals wiih efficiencies, atj 1 whereas no chemical species were formed in Bz; and 2) photoreduction of 3BPby ABs resulted in benzophenone ketyl radical (BPK) formation by benzylic hydrogen abstraction (HA) with efficiencies XHA 1 in 3z and ACN-H2O (4 :1 v/v). The residual efficiency (a: 1 -ET or ! -aH/1) was attributed to a birnolecular process with no photochemical product, which was named 'induced-quenching (IQf. The quenching rate constants (Jcq) of ;'BPby ADs and ABs were less than the diffusion limits of both Bz and AC1~H2O (4 :1 v/v). The net bimolecular rate constants for the ET, HA and IQ processes were estimated from the k values and efficiencies. The rate constants (%T and k,Q) of ET and IQ with AD versus the oxidation potential (￡) of AD followed Rchm-Weller behaviour while logarithmic rate constants {/CHA and ki(j) of HA and IQ by ABs increased linearly with a decrease in the Em of AB. It was suggested, for the deactivation mechanism of 3BPby ABs and ADs (RH), that ;1) the IQ process was intersystem crossing (ISC) enhanced by the partial charge transfer (CT) character of the triplet excipiexes, 3(BP"~- A-RHa + )a,e; (2) radical ion formation by ET might be accomplished in a polar solvent by further CT interaction in the excipiex; (3) the process of BPK formation was inferred to be H-atom transfer in the exciplex, where the more protic H-atom was readily mobile, rather than ET followed by proton transfer and (4) the loss of efficiencies of photochemicalproduct formation was derived not from back ET but from the IQ process, inherent to photoreactions, via triplet excipiexes. The deactivation processes of 3BPby RH are illustrated in Scheme 1. I ET BP'- + RH'(3BP' + RHJcoj -3(BPO- RHg,.-BPK 4 R' BP + RH Scheme 1.

Evaluation of dissociation energies of S-H bonds in thiophenols and thioalcohols on the basis of kinetic measurements

Kinetic data on the reactions of alkyl and benzyl radicals with thiophenol C6H5SH were analyzed within the framework of the parabolic model of transition state. The values of the parameter that establishes a correlation between the activation energy of a reaction and its enthalpy were calculated for reactions of alkyl and benzyl radicals with the C6H5SH. The equations of the parabolic model were used to calculate the bond dissociation energies for 11 thiophenols and 4 thioalcohols. The activation energies for reactions of 12 thiophenoxy radicals with cumene and of C6H5S? radical with several alkyl-aromatic hydrocarbons were obtained.

PHOTOOXIDATIVE CLEAVAGE OF ORGANOSILANES

Avoiding energy wasting return electron transfer reactions remains a central challenge in the design of high efficiency photoinduced electron transfer processes.One strategy for achieving this goal is to utilize compounds which as a result of electron transfer undergo rapid and irreversible chemical reaction in competion with the return electron process.Organosilanes represent a promising class of compounds that may fulfill this requirement.We have found that some organosilanes undergo rapid carbon-silicon bond cleavage when oxidized to their radical cations in photoinduced electron transfer reactions.Interestingly, these radical cation cleavage reactions occur by a rare nucleophile-assisted mechanism.We have investigated the reactivity of different classes of nucleophiles, and have determined the activation parameters for several of these reactions.Keywords: Organosilane, photooxidative cleavage, photoinduced electron transfer, nucleophile, activation energy

Generation of Radical-cations from Naphthalene and Some Derivatives, both by Photoionization and Reaction with SO4-.: Formation and Reactions Studied by Laser Flash Photolysis

Radical-cations from naphthalene and some derivatives have been generated in aqueous acetonitrile both by direct photolysis (with λ 248 nm light via biphotonic ionization) and via reaction with SO4-..The radical-cation reacts rapidly with the parent substrate (k ca. 1E8 dm3 mol-1 s-1) and with nucleophiles (e. g. with N3- k = 4.2*1E9 dm3 mol-1 s-1 or with water, k 4*1E4 s-1 ).The radical-cation from 1-naphthylethanoic acid undergoes rapid decarboxylation (k 5*1E5 s-1).The radical cations from 4-methyl- and 4-methoxy-phenylethanoic acid also rapidly decarboxylate to yield the corresponding benzyl radicals.