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The Cδ -H amination of unactivated, secondary C-H bonds to form a broad range of functionalized pyrrolidines has been developed by a triiodide (I3 (-) )-mediated strategy. By in situ 1) oxidation of sodium iodide and 2) sequestration of the transiently generated iodine (I2 ) as I3 (-) , this approach precludes undesired I2 -mediated decomposition which can otherwise limit synthetic utility to only weak C(sp(3) )-H bonds. The mechanism of this triiodide-mediated cyclization of unbiased, secondary C(sp(3) )-H bonds, by either thermal or photolytic initiation, is supported by NMR and UV/Vis data, as well as intercepted intermediates.

A photoinduced radical cyclization of benzene-tethered 1,7-enynes with Togni reagent in the presence of sodium iodide is developed. Under ultraviolet irradiation, (Z)-4-(iodomethylene)-3-(2,2,2-trifluoroethyl)-3,4-dihydroquinolin-2(1H)-ones are generated in moderate to good yields. The transformation works well without any metals or photo-redox catalysts at room temperature. During the reaction process, the reaction proceeds through a trifluoromethyl radical-triggered α,β-conjugated addition/intramolecular 6-exo cyclization/iodination, with the formation of multiple bonds. Good functional group tolerance is observed under the reaction conditions.

A new method for the synthesis of secondary thiocarbamates from readily available isocyanides and thiosulfonates with broad functional group tolerance is reported. The reaction proceeds under mild reaction conditions in isopropanol and is catalyzed by inexpensive sodium iodide.

The reaction generally proceeds with excellent α-selectivity at the carbonyl group proximal to the more electron-rich aromatic ring.

A reaction of iron(III) chloride with sodium iodide was used to generate iodine for an innovative take on electrophilic cyclization. With ethanol as solvent, the reaction was observed to provide ideal conditions for iodocyclization of 2-alkynylthioanisoles. The fundamental step allows formation of iodine which becomes free to undergo reaction with the starting alkyne to yield the cyclized product. Implementing environmentally benign and simple chemistry, 2-iodosubstituted benzo[b]thiophenes were synthesized in high yields to produce an interesting display of useful molecules.

A catalytic enantioselective Mannich-type reaction of a cyclohexanone-derived alkenyl trichloroacetate with isatin imines was achieved using an (S)-BINOL-derived chiral tin dibromide possessing a 4-tert-butylphenyl group at 3- and 3′-positions as the chiral precatalyst in the presence of sodium methoxide, sodium iodide, and methanol. Optically active 3-alkylated 3-amino-2-oxindoles having up to 90% enantiomeric excess were diastereoselectively obtained in high yields under the influence of the in situ generated chiral tin iodide methoxide.

A method for the iododifluoromethylation of aromatic aldehydes using (bromodifluoromethyl)trimethylsilane (Me3SiCF2Br) is described. The selective formation of the CF2I group is based on using sodium iodide, with the sodium serving as a scavenger of bromide and iodide serving as a nucleophile with respect to difluorocarbene. The primary CF2I-addition products can undergo HI-elimination or iodine/zinc exchange followed by allylation in a one-pot manner.

The iododemetalation succeeds starting from aryl, hetaryl and alkenyl potassium trifluoroborates equipped with a range of functional groups.

Using a catalytic amount of NaI and a stoichiometric oxidant Oxone@, a convenient procedure has been developed for the catalytic oxidative 1,2-shift of arylalkenes in CH3CN/H2O at room temperature, which provides the corresponding α-aryl ketones in moderate to good yields. In this protocol, sodium iodide is first oxidized into hypoiodous acid, which reacts with arylalkene to afford iodohydrin. Then, the iodohydrin is transformed into the α-aryl ketone via an oxidative 1,2-shift rearrangement.

This reaction proceeds with high stereoselectivity to give the title compounds in moderate to good yields.

The study of the reactions of tertiary propargyl alcohols with sodium halides under oxidative conditions is presented. With sodium iodide, α-iodoenones were formed, however, with sodium bromide or chloride the α-haloenones were only formed in low yields under anhydrous conditions. Conversely, upon addition of water to the reaction mixtures, α,α-dibromoketones and α,α-dichloroketones were formed in good yields, but α,α-diiodoketones were not observed.

A facile method for the general synthesis of 2-arylmethylindoles has been developed through the reaction of 2-(2-propynyl)aniline or 2-(2-propynyl)tosylanilide with aryl iodides in the presence of Pd(OAc)2, PPh3, and DBU. 2-(2-Propynyl)tosylanilide is found to be reactive also towards electron deficient alkenes in the presence of Pd(OAc)2 and sodium iodide under an oxygen atmosphere, providing easy access to 2-vinylic indoles which possess exclusive E-stereochemistry in the side chain double bond. Operational simplicity, compatibility of the various functional groups, and ease of product formation are the hallmarks of these methods. A mechanism has been proposed to explain the product formation.

Asymmetric synthesis of optically active cis- and trans-2-aryl-6-methylpyrans from commercially available tetra-O-acetyl-D-glucopyranosyl bromide has been developed. The reaction proceeds by two important steps. One is the arylation, and the other is deoxygenation at the C-3 position and inversion of configuration at the C-2 position during the preparation of the cis-isomer, when 2-aryl-3-hydroxy-6-(hydroxymethyl)pyrans were treated with trimethylsilyl chloride and sodium iodide.

Performing the reaction in EtOH provides esters in yields comparable to those obtained in MeOH.

Treatment of aldehydes with sulfur ylide (CH2=SOMe2 or CH2=SMe2), in the presence of CO2 (1 atm) bubbled sequentially under mild conditions, produces cyclic carbonates in preparative yields. Sodium iodide formed in situ promotes the reaction between epoxide as intermediate and CO2 at ambient conditions, thus constituting a powerful metal-free synthesis of organic cyclic carbonates directly from aldehydes.

The reaction of dithioacetals with excess aqueous hydrogen peroxide in the presence of catalytic amounts of iron(III) acetylacetonate and sodium iodide efficiently produces the corresponding carbonyl compounds in high yields.

The direct synthesis of trifluoromethylindium reagents prepared from trifluoromethyl iodide by using just one equivalent each of indium, lithium chloride or sodium iodide, and ferrocene is reported. The weak In···F interaction is suitable to prepare stable but nucleophilic perfluoroalkyl reagents, which were successfully employed in the perfluoroalkylation of aldehydes. Notably, the nucleophilic trifluoromethylation of various aldehydes took place with trifluoromethyl iodide by utilizing just one equivalent each of indium, lithium chloride, and ferrocene.

A wide variety of organic substrates can be iodinated selectively in good yields by employing a combination of vanadyl acetylacetonate, hydrogen peroxide, and sodium iodide at ice-bath temperature....

A series of 6-(3-aminopropyl)-6H-indolo[2,3-b]quinoxalines were synthesized with high yields by the reaction of 6-(3-chloropropyl)-6H-indolo[2,3-b]quinoxaline and corresponding amines in presence of tetrabutylammonium iodide in boiling toluene or dimethylformamide at room temperature. It was found that boiling of 6-(3-chloropropyl)-6H-indolo[2,3-b]quinoxaline in acetone with sodium iodide or in acetic acid lead to intramolecular cyclization product.

An efficient microwave protocol is described for the Michaelis–Arbuzov synthesis of secondary and tertiary N-aryl (and alkyl) (diethylphosphono)acetamides 1, by reaction of chloro- and bromoacetamides with triethyl phosphite in the presence of catalytic amounts of sodium iodide. Remarkable acceleration of the reaction (minutes vs. several hours) over conventional heating was achieved, together with improved product yields and purity, when bromoacetamides were employed as the substrates. Chloroacetamides were comparatively less reactive, leading to satisfactory yields only when a high excess of the reagent was employed.

The reaction of dithioacetals with 30% hydrogen peroxide in the presence of catalytic amounts of tantalum(V) and iodide ion effectively produced carbonyl compounds in high yields. Dithioacetals also can be deprotected using the niobium(V) catalyzed oxidation of iodide ion by hydrogen peroxide under mild conditions.

The direct azidation of a wide variety of β-dicarbonyl compounds is smoothly achieved with sodium azide using an oxidant in situ generated from sulfonated iodoxybenzoic acid and catalytic amounts of sodium iodide.

The benzylation of hydroxy groups in the presence of tertiary amines is described. A mixture of an alcohol and a benzyl halide afforded the corresponding benzyl ether in good to excellent yields in the presence of diisopropylethylamine. The importance of solventless conditions was observed. The reaction showed high tolerance to many functional groups including benzoate, even at a reaction temperature of 150 °C. Sodium iodide was found to be an efficient catalyst to accelerate the reaction.

The Ruppert—Prakash reagent Me3Si—CF3 is an efficient source of difluorocarbene which is generated by sodium iodide or tetrabutylammonium difluorotriphenylsilicate as the initiator.

In this review, the use of molecular iodine as a catalyst in the synthesis of heterocyclic compounds is presented and reviewed. In recent years, the use of molecular iodine in organic chemistry has received considerable attention because the chemical (a) is inexpen- sive and readily available, (b) is less toxic than alternatives, (c) has an easy workup method, and (d) is a moisture-stable, mild Lewis acid. Many of the reactions using iodine are associated with mild conditions, greater stero- and regioselectivities, short reaction times, and simplicity in their operation. Scheme 1. Iodine is produced from brine in Japan. Chiba Prefecture is the world's largest production site of iodine from brine, which contains iodine species such as NaI mainly in the range of 100-150 ppm concentration. This brine is isolated from the underground, which is a closed system and is not connected to the ocean, together with natural methane gas. Now Japan produces ca. 8000 tons/year of iodine mainly, sodium iodide and potassium iodide, of the ca. 21000 tons/year of iodine production in the world, and most of these iodine species in Japan is produced from the Chiba Prefecture area. World demand for iodine and organic iodine compounds is as follows; X-ray contrast media (21%), disinfectants and biocides (20%), medium of organic reactions (19%), medicinal and pharma- ceuticals (16%), animal feeds (9%), herbicides (4%), photographics (3%), etc. Chemical functional ability of iodine as disinfectants or biocides comes from the oxidizing ability of iodine itself, especially

The reaction of aldehydes with ethylenediamine for the preparation of 2-imidazolines has been studied using hydrogen peroxide as an oxidant in the presence of sodium iodide and anhydrous magnesium sulfate. A mild, green, and efficient method is established to carry out this reaction in high yield.

The unprecedented title reaction proceeds with low catalyst loading (0.5 to 5 mol%), generally high yields (in average 80%) and good functional group tolerance.

hydroxyl groups were converted into nitrate by esters using fuming nitric acid in acetic anhydrideTe5. Benzyl2-U-benzoyl-~-~-arabinopyranoside~ 1, treated with fuming nitric acid in acetic anhydride at 20”, gave benzyl2-O-benzoyl-3,4-di-O-nitro-/3-L-arabinopyranoside 2 (58%) and benzyl2-O-benzoyld-Q-nitro-P-L-arabinopyranoside 3 (3.2%). The isolation of 3, although in Iow yield, suggests that the axial OH-4 group in 1 is more reactive than the equatorial OH-3. This behavior may be due, as has been pointed out7-‘, to intramolecular hydrogen-bonding between OH-4 and O-5, which would enhance the nucleophilic character of OH-4. Treatment of 2 with sodium iodide in acetone”.” afforded partial selective denitration’~12 at O-3, with retention of con~guration and without rearrangement, to give 3. The structure of 3 was confirmed by its transformation into benzyl 2,3-di-0~nzoyl-4-~-nitro-~-L-arabino~yranoside 4 and the subsequent denitration of 4 to give benzyl~,3-di-0-benzoyl-~~L*arabinopyranoside 5, which was identical with the product previously described%. The structure of 5 was confirmed by its reaction with methanesulfonyl chloride to give benzyl 2,3-di-0-benzoyl-4-U-methylsulfonyl-/I-L-arabinopyranoside’.

Treatment of 2-(2,3-epoxy) propylphenyl acetate derivatives with catalytic amounts of NaI in organic solvent gave directly the corresponding 3-chromanyl acetate derivatives in good yields (86.6-98.0%). Similar treatment of 2-(2,3-epoxy) propyl-6-methoxyphenyl N-mesyl-L-phenylalanylate gave a diastereomeric mixture of 8-methoxy-3-chromanyl N-mesyl-L-phenylalanylate, which was fractionated into both diastereomers by silica gel column chromatography. Subsequent hydrolysis of these isomers afforded the enantiomers of 8-methoxy-3-chromanol

Direct iodination of a wide range of phenols may be achieved with unprecedented selectivity in aqueous alcohol solvents by the action of a reagent preparated in situ from sodium hypochlorite and sodium iodide. Para-substituted phenols (or ortho-substituted, when the para-position is already occupied) are obtained in fair to excellent yields by simple isolation techniques. The extent of iodination is easily controlled by stoichiometry. The technique is also useful with some anilines

Bromo- and chloropyridines may be converted to the corresponding iodopyridines by treatment with sodium iodide and acetyl chloride in acetonitrile.

The electrochemical cyclization of dimethyl α,α′-dibromoalkanedioates by making use of a platinum cathode and a copper anode in the presence of sodium iodide gave three- to six-membered dimethyl 1,2-cycloalkanedicarboxylates in good yields.

Symmetrical dimethylsilyl bis-enol ethers are obtained in good yield by reaction of ketones with dichlorodimethylsilane in the presence of triethylamine and sodium iodide. Reaction of ketones with N, N - diethylaminodimethylchlorosilane in the presence of triethylamine and sodium iodide followed by subsequent conversions provides a useful synthesis of silicon-functionalized dimethylsilyl enol ethers including unsymmetrical dimethylsilyl bis-enol ethers

A one-flask conversion of cyclic ketones to N-methyl lactams is described. Reaction of the ketone with triethylorthoformate generates an acetal which is reacted in situ with N-(((p-nitrobenzene)sulfonyl)oxy methylamine 2a(CH3NH-OSO2C6H4NO2). Dealkylation of the resulting O-ethyl imidate with sodium iodide gives the lactam. A variety of lactams, including macrocyclic lactams, are produced simply and in good yields.

Dialkyl, diaryl and alkyl aryl sulfoxides were readily deoxygenated to the corresponding sulfides in excellent yields with titanium(IV) chloride/sodium iodide reagent system at room temperature.

Alkylidenemalonates being electrolyzed in methanol in undivided cell with glassy carbon, carbon or lead cathode in the presence of sodium iodide or sodium bromide are transformed into 3,4-disubstituted cyclobutane-1,1,2,2-tetracarboxylates.

4,5-Dihydro-4,5-dimethylene-1-phenyl-1,2,3-triazole ( 4 ), the 1,2,3-triazole analogue of o -quinodimethane, can be generated in situ from 4,5-bis(bromomethyl) derivative ( 3 ) by sodium iodide induced 1,4-elimination process. By trapping the 1,4-dimethylene-triazole with symmetrically and unsymmetrically substituted dienophiles the Diels-Alder cycloadducts were isolated in moderate to low yields; in the presence of activated molecular sieves the yields are markedly improved.

A convenient synthesis of 1,4-alkadiynes involving condensation of 1-heptyne, 2-propyn-1-ol or methyl 5-hexynoate with propargylic tosylates or chlorides in the presence of copper(I) iodide, sodium iodide and potassium carbonate is described. Due to the mildness of the conditions the method tolerates the presence of various sensitive functional groups in the reacting components

The reaction of 2,2-bis(bromomethyl)biphenyl with tellurium powder and sodium iodide gave the orange compound 1,1-diiodo-2,7-dihydro-3,4-5,6-dibenzotellurepin (1), which is easily reduced with hydrazine hydrate to 2,7-dihydro-3,4-5,6-dibenzotellurepin (2). The latter compound readily forms a black-brown 1:1 complex with TCNQ. The former could be converted to its 1,1-bis(diethyldithiocarbamato)-2,7-dihydro-3,4-5,6- dibenzotellurepin (3) and 1-phenyl-2,7-dihydro-3,4-5,6-dibenzotellurepinium tetraphenylborate (4), respectively, by treatment with NaS2CN(C2H5)2 and NaB(C6H5)4. The UV-vis, IR, ESR and 1H NMR spectral data for the new compounds are presented and discussed.

The reaction of 2,3-disubstituted arylsulfonylaziridines with isocyanates in presence of sodium iodide yielding 4,5-disubstituted-2-imidazolidinones is somewhat specific rather than a general reaction, but whenever the reaction occurs, it does so in a totally stereospecific manner where imidazolidinones produced have the same geometric configuration as that of the starting aziridines. The yield of the imidazolidinones varies (0 to 60%) depending on the nature of the substituent on the aziridine ring carbon as well as their geometry.

The title sugar analogues were synthesized through three routes, by starting with three kinds of 6-O-tosyl-D-fructofuranoses. (i) Treatment of the known 2,3-O-isopropylidene-1,6-di-O-tosyl-β-D-fructofuranose successively with methyl iodide–silver oxide, sodium iodide and diethyl phenylphosphonite provided 6-deoxy-6-[(ethoxy)phenylphosphinoyl]-2,3-O-isopropylidene-4-O-methyl-1-O-tosyl-β-D-fructofuranose in 67% overall yield. This was reduced with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by hydrolysis with acid, to afford a mixture of the 4-O-methyl-1-O-tosyl and 1-deoxy-4-O-methyl derivatives of the title compound. (ii) Treatment of D-fructose with 2-methoxypropene in the presence of TsOH and then with TsCl in pyridine afforded 1,3-O-isopropylidene-6-O-tosyl-α-D-fructofuranose (35% yield). This was subjected to the same five-step conversion, to give the 4-O-methyl derivatives of the title compound. (iii) Treatment of D-fructose with 2,2-dimethoxypropane–SnCl2 and then with TsCl–pyridine gave 1,2-O-isopropylidene-6-O-tosyl-β-D-fructofuranose (23% yield). This was elaborated, in three steps, to either the 3,4-di-O-acetyl-6-deoxy-6[(ethoxy)phenylphosphinoyl] derivative (84%yield) or the 3,4-bis-O-(tetrahydropyran-2-yl) congener (54% yield), both of which furnished, in two steps, the unsubstituted title compound. The products obtained in the three approaches (i–iii) were converted into the corresponding per-O-acetates, whose structures and conformations [2C5(D), 5C2(D), or B3,6] were established by spectroscopy.

Reaction of tittle aziridines with isocyanates in presence of sodium iodide is regiospecific. 2-aryl N-sulfonylaziridines give the 1-N-arylsulfonyl-3-alkyl/aryl-4-phenyl-2-imidazolidinones exclusively whereas the 2-alkyl substituted aziridines afford only the 1-N-alkyl/aryl-3-N-arylsulfonyl-4-alkyl-2-imidazolidinones.

Barbier-type allylation of aldehydes with allylic bromides and tin(II) chloride dihydrate is largely accelerated by adding stoichiometric or substoichiometric amounts of sodium iodide. This method has some merits such as lower temperature, shorter reaction time and/or more choices of solvents for the reaction. Moreover, the activation by the iodide ion enables the use of relatively unreactive allylic chlorides of various structural types (e.g., 3-chloro-2-chloromethylpropene as an isobutene dianion equivalent) and, thus, expands synthetic applicability of this reaction. The major role of the iodide salt is attributed to the in situ generation of the corresponding allylic iodide