2-methyl-3-aryl-propanols

The Friedel-Crafts alkylation of aromatic compounds by oxetanes in the presence of aluminum chloride is mechanistically similar to the solvolyses above, since the first step is electrophilic attack on the ring oxygen by aluminum chloride, followed by a nucleophilic attack on an a-carbon atom by the aromatic compound present. The reaction of 2-methyloxetane and 2-phenyloxetane with benzene, toluene and mesitylene gave 3-aryl-3 -methyl-1-propanols and 3-aryl-3-phenyl-l-propanols as the main products and in good yields (equation 27). Minor amounts of 3-chloro-l-butanol and 4-chloro-2-butanol are formed as by-products from 2-methyloxetane, and of 3-phenyl-l-propanol from 2-phenyloxetane (73ACS3944). 

In that vein, it has been subsequently shown (by reactions which most probably involve a series of one electron transfer processes) that halogens can be stripped from almost any alkyl, alkenyl, or aryl halide by treatment with lithium (Li) or sodium (Na) in the presence of a proton donor such as (commonly used) 2-methyl-2-propanol (r-butanol [(CH3)3C-OH], r-BuOH). A solvent such as oxacyclopentane (THE) helps to moderate the reaction. Rearrangements of the carbon skeleton are common. Because it usually lacks selectivity, the method is only rarely used (unless the goal is destruction of the halogenated compound). 

In general, symmetrical oxo-squaraines having the same end-groups are synthesized by reacting squaric acid with two equivalents of quatemized indolenine, 2-methyl-substituted benzothiazole, benzoselenazole, pyridine, quinoline [39, 45, 46] (Fig. 4) in a mixture of 1-butanol - toluene or 1-butanol - benzene with azeotropic removal of water in presence [39, 45] or absence [47] of quinoline as a catalyst. Other reported solvent systems include 1-butanol - pyridine [48], 1-propanol - chlorobenzene, or a mixture of acetic acid with pyridine and acetic anhydride [49]. Low CH-acidic, heterocyclic compounds such as quatemized aryl-azoles and benzoxazole do not react, and the corresponding oxo-squaraines cannot be obtained using this method [23, 50]. 

There are a number of other aryl-substituted carbodicationic systems that can be properly described as distonic superelectrophiles. For example, dication 45 has been generated from 2,2 -p-phenylenedi-2-propanol in SbFs at —78°C.4 When compared to the dimethyl(phenyl)carbenium ion (cumyl cation) 46, NMR data indicate that the positive charges are dispersed to a considerable extent into the neighboring methyl groups in the dication 45. 

MeS02-PCBs are initially co-extracted from tissue with other OHS and lipids. Lipid-rich tissues such as adipose, liver and lung have been homogenized with dichloromethane (DCM) and n-hexane/2-propanol (3 2) to co-extract lipid and OHS [95,117, 118]. Tissues have also been homogenized with acetone/n-hexane and extracted with n-hexane/diethyl ether or methyl tert-butyl ether (MTBE) [119]. Mammalian adipose and liver and whole fish have been dehydrated with sodium sulfate prior to extraction with n-hexane/DCM (1 1) [11, 96]. Human liver and feces have been extracted with benzene and refluxing by Soxhlet [120], Formic acid has been added to milk samples in preparation for further cleanup [16], After extraction, OHS and aryl methyl sulfones have been separated from lipids by various techniques. Lipid destructive strategies include saponifi-... 

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