Chloride, alkyl intermediate

The phenothiazine duoperone (5) combines structural elements found in phenothiazine and buty-rophenone antipsychotic agents. Alkylation of substituted piperidine 1 with 3-chloropropanol affords the intermediate 2 treatment of this with thionyl chloride converts the terminal hydroxyl to chloride. Alkylation of the phenothiazine 4 with halide 3 affords the antipsychotic agent duoperone (5) [1]. 

Treatment of Af-monosnbstitnted acetamides as well as aryl or alkyl methyl ketoximes 441 with dimethyl(methylene)ammoninm chloride 442 in the presence of phosphorus oxychloride offers two promising, straightforward and generally applicable routes to 2-bis(dimethylaminomethyl)acetamides 443 as a result of the formation of unidoyl chlorides as intermediates (equation 188). 

Vinylidene fluoride is taken up rapidly via the pulmonary route in rats, but at equilibrium the mean concentration (by volume) in rats was only 23% of that in the gaseous phase. Metabolism proceeded very slowly and was saturable at exposure concentrations of about 260 mg/m Its maximum rate was 1% that of vinyl chloride and less than 20% that of vinyl fluoride there has been a report of an increase in the urinary excretion of fluoride in exposed rats. No alkylating intermediate was demonstrated after passage through a mouse-liver microsomal system. However, vinylidene fluoride inhibits mixed-function oxidase activity in vitro and, like similar halogenated compounds that are transformed to reactive metabolites, it alters rat intermediary metabolism, leading to acetone exhalation (lARC, 1986). 

In some cases, the primary ( -4-alkyl intermediates of the type 31 are transformed by traces of hydrogen chloride into the dealkylated intermediates of the type 32 protected only in the sugar moiety. Thus,... 

A number of methods employ an imidazole-2-thione or related compound with a bifunctional reagent to build the thiazine ring in one or two steps. Treatment of (682) with acrylyl chloride directly produced (683) (64JOC1720). Substituting acrylic acid under catalysis allows isolation of the S-alkylated intermediate, which cyclized to (683) upon heating (64JOC1715). 

The active intermediates of these reactions are believed to be titanium enolates formed by the transmetallation with titanium(IV) chloride. Alkylation of enol silyl ethers is also elTected by use of benzyltrimethyl ammonium fluoride, in which quaternary ammonium enolates are produced as intermediates (eq (27)) [24]. 

Hydroformylation with platinum complexes proceeds as described in Scheme 5 when a Lewis acid, e.g., SnCl2, is added. The Lewis acid removes the chloride from the platinum center to afford a vacant coordination site to which the olefins can coordinate. Asymmetric induction occurs during the formation of alkyl intermediates via olefin insertion into the Pt-H bond [8]. Most importantly, the re-gio- and enantioselectivities are strongly influenced by the reaction temperature in the Pt(II)-catalyzed asymmetric hydroformylations [10, 70, 71, 72, 73]. Re-... 

The final palladium-alkyl intermediate can also be trapped by hydride or carbanion reagents87,88,91. In intramolecular versions, this again leads to polycyclic products87,88 91. Thus, palladium-catalyzed polycyclization of aryl iodide 14 containing an enamide and additionally an alkene function leads, with complete stereocontrol, to tricyclic product 15 if the reaction is terminated with sodium formate, phenylzinc chloride or sodium tetraphenylborate (albeit in low yield)45. 

In the most frequently used version, a pyrimidine-2-thione or -thiol (often a 2-thiouracil) was reacted with a bifunctional electrophile containing three carbon atoms. 1,3-Dihalopropane, epichlorohydrin, malonyl chloride, or propargyl bromide served as bifunctional electrophiles. In a few cases, S-alkylated intermediates were isolated. 

G. Gustavson proposed the theory that the aluminium chloride formed intermediate addition compounds of the type AlXsCeHe and AIX3.3C6H6 [J. pr. Chem. 68, 209 (1903)], and that in the course of the reaction these addition compounds reacted with the alkyl halides to form the reaction products. For the preparation of these addition compounds, he passed dry hydrogen chloride into a mixture of aluminium chloride and the hydrocarbon [Ber. 11, 2151... 

When jS-hydrogens are present in the substrate aldehyde, olefins and H2 are produced, but in substantially smaller quantities than observed with analogous acid chlorides. For example, decarbonylation of heptanal yields 14% hexene, whereas exclusive formation of alkene is observed from similar acyl chlorides. This difference is due to the ease with which hydride transfer (as opposed to chloride transfer) occurs in the respective alkyl intermediates. 

In addition, isotopic labeling studies by Bercaw s group provided evidence for irmer-sphere two-electron transfer from R-Pt(ii) to Pt(iv) to form the Pt(iv) alkyl intermediate. Examination of the oxidation of Zeise s salt by [PtCl6] using isotopically labeled Na2[ PtCl6] and analysis via H NMR revealed the Pt satellites for Pt-CH2CH20H to be only 33%, an intensity no greater than the naturally abundant Pt. This was interpreted as evidence for inner sphere, two-electron oxidation via chloride transfer, since an alkyl transfer mechanism would have resulted in an increase in intensity of the Pt satellites relative to natural abundance. 

This includes for example reactivity studies on tra s-[M(N2)2(dppe)2] (98-M M = Mo (98-Mo) and W (98-W)) toward electrophiles such as organic acid chlorides, alkyl hahdes, and inorganic acids.These investigations formed the basis of the so-called Chatt cycle (Scheme 31)" and the intermediates 99-106 involved in the formation of NH3 from N2 have been investigated in detail by computational and spectroscopic methods.However, it is of note that a catalytic turnover has yet to be achieved with these systems. 

Rate constants for the [Fe(phen)3] reactions show Marcus behavior indicative of an outer-sphere process in which reorganization of the metal alkyl is the same regardless of the steric bulk of the R groups. In contrast a marked rate dependence on steric bulk is found for [IrCl6] reactions and the presence of an alternative inner-sphere mechanism is confirmed by the fate of the radical cation [reaction (11)]. In general the rates of these reactions are considerably in excess of Marcus values and a chloride-bridged intermediate (1) is proposed. Detection of such... 

Aromatic hydrocarbons also react smoothly with an equimolar amount of chlorosulfonic acid or an excess of the reagent to yield either the sulfonic acid or the sulfonyl chloride (Equations 6 and 7). The direct conversion of aromatic compounds into their sulfonyl chlorides (chlorosulfonation or chlorosulfonylation) is probably the most important reaction of chlorosulfonic acid because sulfonyl chlorides are intermediates in the synthesis of a wide range of sulfonyl derivatives. The process is of wide application because many substituents on the aromatic ring, e.g. alkyl, alkoxy, amide, carboxy, cyano, hydroxy, nitro and multiple bonds are unaffected by the reagent. 

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