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Alkanes sulfoxidation

The very important factor for the efficient sulfoxidation of alkanes is the partial pressure of sulfur dioxide. The study of alkanes sulfoxidation under S02 pressures higher than 1 atm proves that an optimal temperature exists for alkane sulfoxidation. The data (vmax) on different alkane sulfoxidation are listed below [25], The reaction rate v was the maximal rate measured in the experiment. [Pg.443]

The mechanism of alkane sulfoxidation includes the following elementary steps [13,21 24] initiation, three steps of chain propagation, and a few steps of chain termination. [Pg.444]

In general, peroxomonosulfates have fewer uses in organic chemistry than peroxodisulfates. However, the triple salt is used for oxidizing ketones (qv) to dioxiranes (7) (71,72), which in turn are useful oxidants in organic chemistry. Acetone in water is oxidized by triple salt to dimethyldioxirane, which in turn oxidizes alkenes to epoxides, polycycHc aromatic hydrocarbons to oxides and diones, amines to nitro compounds, sulfides to sulfoxides, phosphines to phosphine oxides, and alkanes to alcohols or carbonyl compounds. [Pg.95]

Extraction Solvent. Dimethyl sulfoxide is immiscible with alkanes but is a good solvent for most unsaturated and polar compounds. Thus, it can be used to separate olefins from paraffins (93). It is used in the Institute Fransais du Pntrole (IFF) process for extracting aromatic hydrocarbons from refinery streams (94). It is also used in the analytical procedure for determining polynuclear hydrocarbons in food additives (qv) of petroleum origin (95). [Pg.112]

Orga.nic Chemistry. The organic chemistry of sulfur dioxide, particularly as it relates to food appHcations, has been discussed (246). Although no reaction takes place with saturated hydrocarbons at moderate temperatures, the simultaneous passage of sulfur dioxide and oxygen into an alkane in the presence of a free-radical initiator or ultraviolet light affords a sulfonic acid such as hexanesulfonic acid [13595-73-8]. This is the so-called sulfoxidation reaction (247) ... [Pg.144]

Carbanions formed from methyl methylthiomethyl sulfoxide 94 and ethyl ethylthio-methyl sulfoxide 95 were shown to be alkylated in excellent yields126,127. Treatment of 94 with rc-BuLi or KH and subsequent reaction with 1, n-dihalo- or bis(tosyloxy)alkane gave 3-, 4-, 5- and 6-membered 1-methylsulfmyl-l-methylthiocycloalkanes128"130. Upon hydrolyses of these products, the corresponding aldehydes and ketones are obtained. [Pg.608]

TABLE 6 Specifications of Sulfoxidation-Derived Alkane-sulfonates (HCils MARLON PS 65)... [Pg.152]

Some other processes are known for sulfoxidation but have no technical importance. The acetic anhydride process has attracted some interest because it does not need exposure to light and enables conversion rates up to 15% of paraffin feedstock. Once started by peroxide or UV light initiation, it propagates without further radical-forming initiation steps. The addition of some 2.5% acetic anhydride to the reacting alkane is crucial to form a mixed anhydride of par-... [Pg.153]

In the homologous series of alkane 1-sulfonates, micellization in aqueous solutions begins with the pentanesulfonate at cM = 1 mol/L. The critical micelle concentrations of the technical alkanesulfonates are cM = 0.002 mol/L (sulfo-chlorination route) and cM = 0.44 g/L (sulfoxidation route). [Pg.193]

The sulfoxidation of aliphatic hydrocarbons is the easiest method for the synthesis of alkylsulfonic acids. Their sodium salts are widely used as surfactive reactants in technology and housekeeping. Platz and Schimmelschmidt [1] were the first to invent this synthetic method. Normal paraffins (Ci4-Cig) are used for the industrial production of alkylsulfonic acids [2-4]. Olefins and alkylaromatic hydrocarbons do not produce sulfonic acids under the action of sulfur dioxide and dioxygen and retard the sulfoxidation of alkanes [5-9],... [Pg.442]

Water retards the sulfoxidation of alkanes [25]. The results of experiments on decane sulfoxidation with addition of water (T=333K, pO2 = 980kPa, [S02]o = 6.2mol L 1, vio=5.0x 10-7 mol L-1 s 1) are given in the following table. The rate of sulfoxidation was observed to increase in time due to the accumulation of alkylsulfonic peracid and, hence, v0 -c vmax. [Pg.444]

The sulfoxidation of alkanes occurs with heat evolution. This is the basis for rate of oscillation of rapid sulfoxidation at a relatively high pressure when the feedback arises between reaction rate, diffusion of reactants into liquid phase, and heat evolution [27],... [Pg.444]

When the hydrocarbon concentration is high enough for the reaction of the sulfonyl-peroxyl radical with hydrocarbon not to limit the chain propagation, the following equation describes the dependence of the initial rate v of initiated (Vj) chain sulfoxidation of alkane [25] ... [Pg.445]

MA Saitova. Kinetics and Mechanism of Sulfoxidation of Alkanes. Ph.D. thesis, Institute of Chemical Physics, Chernogolovka, 1975. [Pg.454]

Sulfur dioxide undergoes sulfoxidation and suUbchlorination with alkanes. [Pg.897]

Recently, Punniyamurthy and co-workers applied the same catalyst 5a as used for the oxidation of alkanes [152] (Sect. 4.2) for the selective oxidation of aromatic sulfides to the corresponding sulfoxides with H2O2 (Eq. 19) [236]. Addition of 5 mol % TEMPO dramatically improved the selectivity and conversion with methylphenylsulfide as the substrate, only traces of sulfone were observed. [Pg.60]

A very interesting synthetic method of bicyclo[n.l.O]alkanes from cychc ketones via this 1,3-C,H insertion of magnesium carbenoid as a key reaction was reported (equation 22) . 1-Chlorovinyl p-tolyl sulfoxide (76) was synthesized from cyclopentadecanone and chloromethyl p-tolyl sulfoxide in three steps in high overall yield. Lithium enolate of tert-butyl acetate was added to 76 to give the adduct 77 in quantitative yield. a-Chlorosulfoxide (77) in a toluene solution was treated with i-PrMgCl in ether at —78 °C and the reaction mixture was slowly warmed to 0°C to afford the bicyclo[13.1.0]hexadecane derivative 79 in 96% yield through the reaction of the intermediate magnesium carbenoid 78. [Pg.733]

The synthesis of bicyclo[n. 1.0]alkanes (82) from various 1-chlorovinyl p-tolyl sulfoxides (80) and lithium enolate of ieri-butyl acetate, propionate and hexanoate through the adducts (81) are summarized in Table 3. As shown in Table 3, addition reaction of tert-butyl carboxylates to 1-chlorovinyl p-tolyl sulfoxides (80) proceeds smoothly to afford the adducts (81) in high to quantitative yields. Cyclopropanation of 81 with i-PrMgCl... [Pg.733]

TABLE 3. Synthesis of bicyclo [ .1.0]alkanes (82) from 1-chloro-vinyl p-tolyl sulfoxides (80) with lithium enolate of tert-butyl acetate, propionate and hexanoate through the adduct (81)... [Pg.733]


See other pages where Alkanes sulfoxidation is mentioned: [Pg.442]    [Pg.443]    [Pg.2032]    [Pg.2032]    [Pg.2042]    [Pg.2042]    [Pg.2032]    [Pg.2042]    [Pg.2042]    [Pg.1038]    [Pg.12]    [Pg.442]    [Pg.443]    [Pg.2032]    [Pg.2032]    [Pg.2042]    [Pg.2042]    [Pg.2032]    [Pg.2042]    [Pg.2042]    [Pg.1038]    [Pg.12]    [Pg.108]    [Pg.95]    [Pg.137]    [Pg.6]    [Pg.146]    [Pg.152]    [Pg.496]    [Pg.107]    [Pg.114]    [Pg.68]    [Pg.64]    [Pg.279]    [Pg.407]    [Pg.150]   
See also in sourсe #XX -- [ Pg.12 ]




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