Alicyclic hydrocarbons preparation

Although aliphatic and alicyclic hydrocarbons react with most sul-fonating agents, the reactions are not suitable for the preparation of the pure sulfonic acids. " Certain olefins react with sulfur dioxide-dloxane complex to give olefinic sulfonic acids In this way, cyclohexene is converted to l-cyclohexene-3-sulfonic acid, whereas with concentrated sulfuric acid in a mixture of acetic acid and acetic anhydride the main product is 2-hydroxycyclohexanesuIfonic acld. 1-Propene-l-sulfonic acid is obtained in low yield by the action of oleum on n- or isopxopyl alcohol. ... 

A significant number of works are concerned with the development of new membranes for the separation of mixtures of aromatic/alicyclic hydrocarbons [10,11,77-109]. For example, the following works can be mentioned. A mixture of cellulose ester and polyphosphonate ester (50 wt%) was used for benzene/cyclohexane separation [113]. High values of the separation factor and flux were achieved (up to 2 kg/m h). In order to achieve better fluxes and separation factors the attention was shifted to the modification of polymers by grafting technique. Grafted membranes were made of polyvinylidene fluoride with 4-vinyl pyridine or acrylic acid by irradiation [83]. 2-Hydroxy-3-(diethyl-amino) propyl methacrylate-styrene copolymer membranes with cyanuric chloride were prepared, which exhibited a superior separation factor /3p= 190 for a feed aromatic component concentration of 20 wt%. Graft copolymer membranes based on 2-hydroxyethyl methylacrylate-methylacrylate with thickness 10 pm were prepared [85]. The membranes yielded a flux of 0.7 kg/m h (for feed with 50 wt% of benzene) and excellent selectivity. Benzene concentration in permeate was about 100 wt%. A membrane based on polyvinyl alcohol and polyallyl amine was prepared [87]. For a feed containing 10 wt% of benzene the blend membrane yielded a flux of 1-3 kg/m h and a separation factor of 62. 

Preparation of alicyclic hydrocarbons from other aliphatic compounds generally involves two stages (a) conversion of some open-chain compound or... 

Alicyclic hydrocarbons are prepared from other cyclic compounds (e.g. halides or alcohols) by exactly the same methods that are used for preparing open-chain hydrocarbons from other open-chain compounds. 

Dehydrogenation (the conversion of alicyclic or hydroaromatic compounds into their aromatic counterparts by removal of hydrogen and also, in some cases, of other atoms or groups) finds wide application in the determination of structure of natural products of complex hydroaromatic structure. Dehydrogenation is employed also for the synthesis of polycyclic hydrocarbons and their derivatives from the readily accessible synthetic hydroaromatio compounds. A very simple example is the formation of p-methylnaphthalene from a-tetra-lone (which is itself prepared from benzene—see Section IV, 143) ... 

Wibaut, J. P., Overhoff, J., and Jonker, E. W., Ibid., 62, 31-45 (1943). On the Preparation of Some Hydrocarbons of the Mixed Aliphatic-Aromatic or Aliphatic-Alicyclic Type Containing 22 to 38 C-Atoms. 

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