Subject with thionyl chloride

Earlier it was indicated (Schemes 5, 7, 10) that the hydroxy acetate (42) was transformed into the drimenol (2) [49], its acetate (12) [42] or a mixture of the drimenol (2) and the albicanol (43) [39]. Authors [55] accomplished the targeted synthesis of the albicanol (43) and its acetate (68) starting with the hydroxy acetate (42) (Scheme 12). The hydroxy acetate (42) was dehydrated with thionyl chloride into the mixture of acetates (12), (67) and (68), which was subjected to oxidation with m-CPBA. On that treatment the acetates (12) and (67) are selectively oxidised, but the acetate (68) remained unreacted. The latter was than isolated by chromatography and saponified into the albicanol (43). The overall yield of the albicanyl acetate (68) and the albicanol (43) was 61% (at the saponification step the yield of (43) was quantitative). Barrero et al. 

Ethyldiphenylphosphine oxide 397 Diphenylphosphinic acid (0.22 g) is converted into the acid chloride by 1-2 hours boiling under reflux with thionyl chloride (0.5 ml) in toluene. About half the solvent is then distilled off and the residual solution is diluted with benzene and dropped at room temperature into a Grignard solution prepared from magnesium (0.25 g) and ethyl bromide (2.5 ml). The reaction is complete after half an hour s boiling under reflux. The product is hydrolysed by ice and hydrochloric acid, the aqueous layer is washed with ether, and ether phases are united, dried, and evaporated. The residue is subjected to steam-distillation and then extracted several times with ether. The residue left on evaporation of these extracts crystallizes at once or on short storage and is decolorized in acetone by charcoal. Recrystallization from ether-light petroleum or aqueous acetone affords the oxide, m.p. 123-124° (67%). 

Sulfonic acids may be subjected to a variety of transformation conditions, as shown in Figure 2. Sulfonic acids can be used to produce sulfonic anhydrides by treatment with a dehydrating agent, such as thionyl chloride [7719-09-7J. This transformation is also accomphshed using phosphoms pentoxide [1314-56-3J. Sulfonic anhydrides, particulady aromatic sulfonic anhydrides, are often produced in situ during sulfonation with sulfur trioxide. Under dehydrating conditions, sulfonic acids react with substituted aromatic compounds to give sulfone derivatives. 

Cholesterol, glycyrrhetic acid acetate Apply sample solution and moisten with anhydrous benzene, subject for 4 h to the vapors of thionyl chloride — benzene (1 -I-1) in a desiccator, then dry and develop. A chlorinated cholesterol or the chloride of 3- -acetoxyglycyrrhetic acid are formed. [16]... 

To 1.17 g of (-)-7,8-difluoro-2,3-dihydro-3-hydroxymethyl-4H-[l,4] benzoxazine was added 2.77 g of thionyl chloride in pyridine. The reaction mixture was concentrated and the concentrate was subjected to column chromatography using 40 g of silica gel and eluted with chloroform to obtain 1.18 g of the reaction product as a colorless oily product. This product was dissolved in 30 ml of dimethyl sulfoxide, and 0.41 g of sodium borohydride was added thereto, followed by heating at 80-90°C for 1 hour. The reaction mixture was dissolved in 500 ml of benzene, washed with water to remove the dimethyl sulfoxide, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The concentrate was subjected to column chromatography using 40 g of silica gel and eluted with benzene to obtain 0.80 g of (-)-7,8-difluoro-2,3-dihydro-3-methyl-4H-[l,4]benzoxazine as a colorless oily product [a]D25 = -9.6° (c = 2.17, CHCI3). Optical Purity >99% e.e. 

Diethyl difluoroalkylphosphonates (235), when subjected to chlorination by thionyl chloride, are smoothly transformed into difluoroalkylphosphonyl dichloride (236). Esterification of the latter with different thiols under basic conditions delivers new difluoroalkylphosphonodithioates (237) in good yield. Exposure of these compounds to Lawesson s reagent converts P=0 into P=S giving new difluoroalkylphosphonotrithioates (238) (Scheme 65)." ... 

A novel synthetic approach was developed by R.E. Taylor et al. for the preparation of the triene portion of the biologically active polyketide apoptolidin. The allylic chloride substrate was prepared from an allylic alcohol via a thionyl chloride mediated rearrangement. Next, the allylic chloride was subjected to the Ganem oxidation by treating it with five equivalents of trimethylamine A/-oxide (TMANO) in DMSO at room temperature to obtain the desired a,p-unsaturated aldehyde. Interestingly, the original Kornblum oxidation conditions were not well suited for this system because of the required high reaction temperature. 

The acids are stable compounds which readily form salts, and are subject to decarboxylation and conversion into acid derivatives with the usual reagents. Acid chlorides are usually made with phosphoryl chloride <82JHC56l> or thionyl chloride <84SC251,85JHC413). 

The rate of this process in aprotic electrolytes is rather high the exchange current density is fractions to several mA/cm. As pointed out already, the first contact of metallic lithium with electrolyte results in practically the instantaneous formation of a passive film on its surface conventionally denoted as solid electrolyte interphase (SEI). The SEI concept was formulated yet in 1979 and this film still forms the subject of intensive research. The SEI composition and structure depend on the composition of electrolyte, prehistory of the lithium electrode (presence of a passive film formed on it even before contact with electrode), time of contact between lithium and electrolyte. On the whole, SEI consists of the products of reduction of the components of electrolyte. In lithium thionyl chloride cells, the major part of SEI consists of lithium chloride. In cells with organic electrolyte, SEI represents a heterogeneous (mosaic) composition of polymer and salt components lithium carbonates and alkyl carbonates. It is essential that SEI features conductivity by lithium ions, that is, it is solid electrolyte. The SEI thickness is several to tens of nanometers and its composition is often nonuniform a relatively thin compact primary film consisting of mineral material is directly adjacent to the lithium surface and a thicker loose secondary film containing organic components is turned to electrolyte. It is the ohmic resistance of SEI that often determines polarization of the lithium electrode. 

Reasoning that torsional factors in the trioxa-trans-decaline moiety could have had an effect on the regioselectivity of the hydroxyl elimination (10), we prepared compound 7 from 4. The benzylidene ring in 4, was hydrolyzed in acetic acid solution, and the resulting free hydroxyl groups benzoylated to afford monocyclic product 7. When compound 7 was subject to the same thionyl chloride treatment only the product with the desired regiochemistry, 8, was observed. 

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