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Received: 25.03.22. Revised: 24.05.22. Accepted: 24.05.22. Available online: 30.05.22. The composition of the reaction mixture after DTTA tert-butyl ester alkylation with 6'-halomethyl-5-phenyl-2,2'-bipyridines was studied. In addition to the target product, DTTA-appended 2,2’-bipyridine, the corresponding 6'-hydroxymethyl-substituted 2,2’-bipyridine and (5'-phenyl-[2,2'-bipyridin]-6-yl)methyl formate were isolated as byproducts in some cases. Finally, an improved procedure for the DTTA tert-butyl ester alkylation with 6'-halomethyl-5-phenyl-2,2'-bipyridines by using Finkelstein reaction was developed. This work was supported by the Russian Science Foundation (grant no. 18-73-10119-P).

New eco-friendly conditions for Finkelstein reaction employing homogeneous media or alumina-supported reagents, both solventless, were utilized in the bromohydrins and iodohydrins synthesis from 1,3-dichlorohydrin (1,3-DCH), obtained from glycerol. Thus, the trans-halogenation of glycerol-1,3-dichlorohydrin (1) in homogeneous media, using NaI, NaBr salts and organic additives (TBAI, TBAB), led to the synthesis of four different glycerol halohydrins (2a, 2b, 3a, 3b) in regular to excellent conversions (43–96%) and good selectivities to 3a and 2b. Already, the alumina-supported reagents such as KI, KBr, NaBr were used for glycerol-1,3-dichlorohydrin trans-halogenation, in the absence of solvent, producing halohydrin mixtures in high conversions (77–99%) and very good selectivity (82%) to 1,3-diiodo-2-propanol (2b).

Preparative procedure for 4,5-bis(diethoxyphosphorylmethyl)-3-furoate from 4-chloromethyl-3-furoate is developed. It includes substitution of chlorine with iodine, phosphorylation by means of the Arbuzov reaction, chloromethylation of 4-(diethoxyphosphorylmethyl)-3-furoate in the position 5 of the furan ring, substitution of chlorine with iodine in the obtained chloromethyl derivative, and repeated phosphorylation with triethyl phosphite. It was found that ethyl 4-(diethoxyphosphorylmethyl)-5(chloromethyl)-3-furoate reacts with sodium diethyl phosphite by two pathways. Besides usual nucleophilic substitution leading to phosphonate, transfer of the reaction center in the position 2 of the furan ring takes place. The ambident diethylphosphite anion in this case reacts at the oxygen to give tertiary phosphite. The latter is oxidized with the air oxygen to form ethyl 2-(diethoxyphosphoryloxy)-4-(diethoxyphosphorylmethyl)-5-methyl-3-furoate. Unlike that analogous iodomethyl phosphonate is phosphorylated selectively under the conditions of the Arbuzov reaction.

The facile iodination of aromatic compounds under mild conditions is a great challenge for both organic and medicinal chemistry. Particularly, the synthesis of functionalized aryl iodides by light has long been considered impossible due to their photo-lability, which actually makes aryl iodides popular starting materials in many photo-substitution reactions. Herein, a photo-induced halogen exchange in aryl or vinyl halides has been discovered for the first time. A broad scope of aryl iodides can be prepared in high yields at room temperature under exceptionally mild conditions without any metal or photo-redox catalysts. The presence of a catalytic amount of elemental iodine could promote the reaction significantly.

A general, rapid, and efficient method for the copper-catalyzed Finkelstein reaction of (hetero)aromatics has been developed using continuous flow to generate a variety of aryl iodides. The described method can tolerate a broad spectrum of functional groups, including N-H and O-H groups. Additionally, in lieu of isolation, the aryl iodide solutions were used in two distinct multistep continuous-flow processes (amidation and Mg-I exchange/nucleophilic addition) to demonstrate the flexibility of this method.

N (ω-Haloalkyl)amidothiophosphates, N (ω-Haloalkyl)amidothiophosphonates, and N- (ω-Haloalkyl)amidothiophosphinates (Hal = Cl or Br) were obtained in high yields by alkylation of phosphorus(V) acid thioamides with 6h,ω-dihaloalkanes under phase-transfer catalysis (PTC) conditions or through the use of NaH as a base. Thermal rearrangement of N (3-iodopropyl)-or N (4-iodobutyl)amidothiophosphate and N (3-iodopropyl)-or N (4-iodo-butyl)amidothiophosphonate obtained in situ by the Finkelstein reaction provides a convenient route to 2-oxo-1,3,2-thiazaphosphinanes and 2-oxo-1,3,2-thiazaphosphepanes. Reactions of N (ω-Haloalkyl)amidothiophosphinates with NaClO4 in MeCN afforded the first example of stable 1,3,2-thiazaphosphacyclanium salts containing P—C bonds.

International audience; The radical copolymerisation of electron-acceptor chlorotrifluoroethylene (CTFE) with electron-donorvinyl ethers (VEs) produced poly(CTFE-alt-VE) alternating fluorinated copolymers with a high content offunctional groups. This article describes methods to synthesise poly(CTFE-alt-VE) copolymers that bearammonium-groups insensitive to Hofmann degradation. Direct preparation and post-polymerisationfunctionalisation methods are presented. First, the radical copolymerisation of CTFE with a tertiaryamine-carrying vinyl ether led to low molecular weight-copolymers with an imperfect structure. Thatcopolymerisation and the quaternisation of the amino groups using methyl iodide were howeveraccompanied by side reactions, including transfer reactions and significant loss of functionality. Incontrast, the second strategy dealt with the post functionalisation of an alternated poly(CTFE-alt-2-chloroethyl vinyl ether) copolymer. Halogen exchange of poly(CTFE-alt-CEVE) copolymers was carriedout using the efficient Finkelstein reaction. Then, the nucleophilic substitution of the iodine atoms on theobtained poly(CTFE-alt-IEVE) copolymer led to a poor yield of functionalisation and was accompaniedby a substantial amount of side reactions. Then, the iodine atoms in poly(CTFE-alt-IEVE) copolymerswere chemically changed quantitatively into azides (especially from microwave activation) and theresulting azido-containing copolymer was reacted with 1-dimethylamino-2-propyne. An optimisation ofthis Huisgen's or thermal cycloaddition showed that (i) a copper catalyst led to cross-linked copolymers,(ii) whereas in the absence of the copper catalyst, the cycloaddition was slow and only converted ca.60% of the azides; (iii) then, microwave activation led to high yield in a few minutes. Dimethylaminogroups were inserted onto the copolymeric backbone and subsequently quaternised using iodomethaneefficiently. Such copolymers, potentially resistant to alkaline media and able to promote hydroxide anionconduction, may exhibit interesting properties as a component of solid alkaline fuel cell membranes.

The synthesis of several omega-chloroalkyl tetrazoles and their subsequent attachment to a solid support is described. Using an in situ Finkelstein reaction, a variety of nucleophiles were alkylated and then cleaved from the resin to give pure alkyl tetrazole derivatives. A sample library of 5 x 6 demonstrates the general utility of this sequence.

A novel and efficient method of synthesis of 3-substituted derivatives of pentane-2,4-dione is proposed, wherein cheaper and easily accessible chloro derivatives are conversed into more reactive iodo derivatives. The method is based on the Finkelstein reaction for which the literature suggests highly polar organic solvents as ideal reaction media. In the presented work, the use of industrially used ketones, especially methyl isobutyl ketone, is proposed. The use of MIBK as a solvent additionally allows an azeotropic removal of water from the reaction mixture, enabling the application of moisture sensitive alkylating agents i.e. (3-chloropropyl)trimethoxysilane. The obtained products are isolated through distillation, which does however not allow the separation of C-alkylation products from O-alkylation ones. The products not containing water-sensitive substituents were isolated as copper complexes. The pure product of C-alkylation was obtained by decomposition of the copper complex with a hydrochloric acid solution and extraction of the formed ligand to an organic phase i.e. hexane. The obtained ligand can be further purified by distillation.

Solutions of the fluorous alkyl halides R(f8)(CH(2))(m)X (R(fn)=(CF(2))(n-1)CF(3); m=2, 3; X=Cl, Br, I) in perfluoromethylcyclohexane or perfluoromethyldecalin are inert towards solid or aqueous NaCl, NaBr, KI, KCN, and NaOAc. However, halide substitution occurs in the presence of fluorous phosphonium salts (R(f8)(CH(2))(2))(R(f6)(CH(2))(2))(3)P(+)X(-) (X=I (1), Br (3)) and (R(f8)(CH(2))(2))(4)P(+)I(-) (10 mol %), which are soluble in the fluorous solvents under the reaction conditions (76-100 degrees C). Stoichiometric reactions of a) 1 with R(f8)(CH(2))(2)Br and b) 3 with R(f8)(CH(2))(2)I were conducted under homogenous conditions in perfluoromethyldecalin at 100 degrees C and yielded the same R(f8)(CH(2))(2)I/R(f8)(CH(2))(2)Br equilibrium ratio ( approximately 60:40). This shows that ionic displacements can take place in extremely nonpolar fluorous phases and suggests a classical phase-transfer mechanism for the catalyzed reactions. Interestingly, the nonfluorous salt (CH(3)(CH(2))(11))(CH(3)(CH(2))(7))(3)P(+)I(-) (4) also catalyzes halide substitutions, but under triphasic conditions with 4 suspended between the lower fluorous and upper aqueous layers. NMR experiments established very low solubilities in both phases, which suggests interfacial catalysis. Catalyst 1 is easily recycled, optimally by simple precipitation onto teflon tape.

A mild and general method for the conversion of aryl, heteroaryl, and vinyl bromides into the corresponding iodides was developed utilizing a catalyst system comprising 5 mol % of CuI and 10 mol % of a 1,2- or 1,3-diamine ligand. A variety of polar functional groups are tolerated, and even N−H containing substrates such as sulfonamides, amides, and indoles are compatible with the reaction conditions. Both the reaction rate and the equilibrium conversion of the aryl bromide depend on the choice of the halide salt and the solvent. The best results were obtained using NaI as the halide salt and dioxane, n-butanol, or n-pentanol as the solvents.

A fast and efficient nickel-catalysed iodination reaction of aryl and heteroaryl bromides has been developed. The transformation was found to be general for a wide range of substrates and was used for the synthesis of iodo-PK11195, an imaging agent of Alzheimer's disease and iniparib, a compound used in the treatment of breast cancer.

Two essential concepts for students to grasp in the undergraduate organic chemistry sequence are substitution chemistry and elimination chemistry (SN1/SN2 and E1/E2). However, students are often confounded by the seemingly endless series of structure–reactivity relationships. This dualistic relationship of conceptual essentialness and student confusion usually results in a line of demarcation for many second-year organic chemistry students. It is at this point that students either pull together the fundamental structure–reactivity relationships and go on to draw relevant mechanistic conclusions that underpin the balance of their organic chemistry experience or the flood of material washes over them and they wind up in a miserable struggle to keep their heads above water until the end of the spring semester. Therefore, we have developed a quantitative kinetics laboratory exercise featuring the Finkelstein reaction (SN2) for use in the first-semester organic chemistry course that utilizes nonaqueous conduct...

The rate constant of the reaction of methyl iodide with the bromide ion showed a characteristic dependence on the composition of solvent mixtures. In five solvent mixtures, i.e., acetonitrile–ethylene glycol, –1,2-propanediol, –1,3-butanediol, –1,4-butanediol, and –2,3-butanediol, its dependence was fairly well reproduced by the theoretical equations derived on the basis of the concept of the concurrent monodentate and bidentate solvation of the halide ion by glycol. In contrast, the rate constants in acetonitrile–diethylene glycol and –triethylene glycol mixtures were better reproduced by the modified theoretical equations allowing for a self-association of glycol.

Chlorine isotopic exchange reactions of substituted chloromethanes [(arylsulfonyl)chloromethanes (1), (arylsulfinyl)chloromethanes (2), and 2-chloro-1-arylethanones (4)] with tetraethylammonium chloride-36Cl were studied in acetonitrile. This study enabled, for the first time, the accurate rate study of the former two classes of compounds (1 and 2) of extremely low reactivity. Both the large enthalpies of activation and the positive entropies of activation were the characteristics for these two substrates (1-p-NO2 and 2-p-NO2). High reactivity of 2-chloro-1-phenylethanone was substantiated, and was not associated with the significant secondary kinetic deuterium isotope effect. A nucleophile-substrate association that proceeds the reaction was suggested and the possible role of such an interaction was examined in the light of the intermediary of the nucleophile-substrate complex in the Finkelstein reaction.

The Finkelstein reaction has been studied in five dipolar aprotic–dipolar aprotic solvent mixtures and one protic-dipolar aprotic solvent mixture. The theoretical equations for the rate constant as a function of solvent composition derived previously have been reformulated in terms of the solvent exchange model on the solvation site, taking into account the two main features of solvation: the number of the solvation sites on the solvent molecule and the equilibrium constant for the solvent exchange process. The results obtained previously, together with present results, are comprehensively discussed and the solvent mixtures are classified into four groups from the viewpoint of solute-solvent interaction in the region near the ion, using derived theoretical equations.

A specific type of reaction should have a characteristic isokinetic temperature as long as the individual reactions are carried out in the same solvent and the reactions of substrates with bulky groups are excluded. Two kinds of reactions of tertiary amine with carboxylates, quaternization and aminolysis reactions, were distinguished by isokinetic temperatures of 430 and 256, respectively.

Synthesis of p-bromomethylstyrene (3) and p-iodome-thylstyrene (4) is reported. 3 was obtained by the bromomethylation of 2-phenylethyl bromide followed by dehydrobromination of the resultant p-(2-bromoethyl) benzyl bromide (2) with t-BuOK, as well as by cleaving p-vinyl-benzyl methanosulfonate with LiBr in the presence of 18--crown-6. 4 was obtained from p-chloromethylstyrene (1) via the Finkelstein reaction. 3 was polymerized successfully in the presence of free-radical initiators, but 4 was found to be too unstable to give a well-defined polymer.

The rate constants were determined for both processes of the Finkelstein reaction in acetonitrile–alcohol mixtures at 30 °C:CH_3Br+I^-\oversetk_f\undersetk_r\ightleftarrowsCH_3I+Br^-Theoretical equations were derived describing the dependence of the rate constant on the composition changes in the solvent mixtures. These equations describe the change in the rate constant in terms of changes in the activity coefficient. The results were analyzed by means of the equations; they lead to the conclusion that anions have multiple solvation equilibria with alcohols. The relative magnitudes of the step-by-step association constants and of the solvation numbers thus determined agreed with the results determined spectrophotometrically.

Substrate-nucleophile association was found between substituted chloromethanes (ArXCH2Cl: X=NONE, S, SO, SO2, and CO) and halide ion (Cl−, Br−, and I−) in dipolar aprotic solvent. The equilibrium constant (K), limiting shift (Δc), the enthalpy of formation (ΔH°), and the entropy of formation (ΔS°), for complexing were determined by NMR measurement. The measurement of spin-lattice relaxation time (T1) gave an information on the conformation of this complex. Halide ion seems to locate closest to α-methylene protons at the site of potential SN2 reaction.