17203-41-7

Upstream product

• 108-99-6 3-Methylpyridine 
• 62-53-3 Aminobenzenradikatkation 
• 105384-19-8 C₄H₉S₂⁽¹⁺⁾ 
• 4104-83-0 3-methylpyridine borane complex 
• 15454-31-6 iodate 

Downstream Products

• 2315-39-1 1-hexadecyl-3-methylpyridinium bromide 
• 108-99-6 3-Methylpyridine 

Relevant academic research and scientific papers

Steric and kinetic isotope effects in the deprotonation of cation radicals of NADH synthetic analogues

The deprotonation rate constants and kinetic isotope effects of the cation radicals have been determined by combined use of direct electrochemical techniques at micro- and ultramicroelectrodes, redox catalysis, and laser flash photolysis, over a extended

Experimental and Theoretical Studies of the Gas-Phase Protonation of Vinyl Ethers, Vinyl Sulfides, and Vinyl Selenides

A series of nine chalcogen-substituted ethylenes (chalcogen = O, S, Se) have been synthesized, and their gas-phase proton affinities (PA) were determined experimentally by measuring gas-phase basicities (GB) in an ion cyclotron resonance (ICR) spectrometer and theoretically by means of ab initio MO calculations at the STO-3G and 3-21G* levels.A satisfactory correlation (r = 0.978, slope = 1.41) has been obtained between the experimental and calculated 3-21G(*) values.In contrast with a number of previous reports, we consistently found that third- (SMe) and fourth-row (SeMe) substituents do not stabilize better the adjecent positive charge than does the second-row substituent OMe, even in the gas phase.In fact, comparison of experimental proton affinity value of ethylene with that of mono(methylchalco)ethylenes indicates that OMe, SMe, and SeMe groups stabilize the corresponding ethyl cations to very much the same extent.In 2-propyl cations the trend is O > S > Se, but the differences (δΔ in Table III) are quite small: 1.2 kcal mol-1 between O and S and 1.4 kcal mol-1 between S and Se.The superior ability of oxygen in carbenium ion stabilization appears the most clearly in the protonation of bis(methylchalco)ethylenes: dimethoxyethyl cation is more stable than the corresponding thio species by ca. 5.5 kcal mol-1, whereas dithio- and diselenocarbenium ions again have very similar stabilities.These conclusions are supported and extended by ab initio results on optimized geometries.

Carbon-Hydrogen Bond Dissociation Energies in Alkylbenzenes. Proton Affinities of the Radicals and the Absolute Proton Affinity Scale

Rate constants (k) were measured for proton-transfer reactions from alkylbenzene ions RH+ to a series of reference bases B, i.e., RH+ + B -> BH+ + R*.For exothermic reactions (ΔH -1.For example, the reaction C6H5CH3+ + B -> BH+ + C6H5CH2* is fast (reaction efficiency = k/kcol >/= 0.5) when B = MeO-t-Bu or stronger bases, but k/kcol is significantly smaller when B is n-Pr2O or weaker bases.From the falloff curve of reaction efficiency vs.PA(B), we find PA(n-Pr2O) = PA(C6H5CH2*) + 0.8 kcal mol-1 = 200.0 kcal mol-1.Since PA(C6H5CH2*) is obtained from known thermochemical data, this relation defines the absolute PA of n-Pr2O.Through a ladder of known PA, we then obtain PA(i-C4H8) = 186.8 kcal mol-1; we also obtain the absolute PAs of other oxygen bases.Falloff curves of reaction efficiencies of 3-FC6H4CH3+, C6H5C2H5+, C6H5-n-C3H7+, and C6H5-i-C3H7+ with these reference bases give then the following PAs of R* and R-H bond dissociation energies (Do) (all in kcal mol-1) as R*, PA(R*), Do(R-H): 3-FC6H4CH2*, 197.2, 89.4; , 197.9, 86.2; , 199.1, 86.1; , 199.6, 86.1.In similar manner, rate constants for H+ transfer from C6H5NH2+ to reference pyridines and amines yield PA(C6H5NH*) = 221.5 and Do(C6H5NH-H) = 85.1 kcal mol-1 (1 kcal mol-1 = 4.18 kJ mol-1).

Amine boranes. III. Propanolysis of pyridine boranes

The solvolysis kinetics in 1-propanol of a number of alkyl-substituted pyridine boranes was studied. The reactions were first order in amine borane. Linear variation of log k with pKa of the pyridinium ion was observed for groups of compounds with the same ortho substituents; steric enhancement of rate was attributed to 1.1 and 3.5 kcal./mole of strain relief in the transition state for one or two o-methyl groups, respectively. It was concluded that the solvolysis mechanism involves B-N cleavage in the slow step. It was found that the free energy of the transition state referred to the dissociation products was invariant with substitutions on the pyridine ring.