5.5- dichloro dimethyl sulfoxide

Poraij-Koshits MA (1978) Structural effects of mutual influence of ligands in transition- and non-transition-metal complexes. Koordinatsionnaya Khimiya 4 842-866 (in Russian) Hartley FR (1973) The cis- and trans-effects of ligands. Chem SocRev 2 163-179 Russell DR, Mazid MA, Tucker PA (1980) Crystal structures of hydrido-tris(triethyl-phosphine)platinum(II), fluoro-tris(triethylphosphine)platinum(lD, and chloro-tris(trieth-ylphosphine)platinum(II) salts. J Chem Soc Dalton Trans 1737-1742 Blau R, Espenson J (1986) Correlations of platinum-195-phosphorus-31 coupling constants with platinum-hgand and platinum-platinum bond lengths. Inotg Chem 25 878-880 Belsky VK, Konovalov 1, Kukushkin VYu (1991) Structure of cis-dichloro-(dimethyl-sulfoxide)-(pyridine)platinum(II). Acta Cryst C47 292-294... 

ClaHi8Cl2N202Zn, Dichlorobis(2,6-lutidine N-oxide)zinc(II), 33B, 458 C1 aH2 2ClijCu2N20i S2, Di-jU (pyridine oxide)-bis(dichloro(dimethyl sulfoxide)copper(II)), 41B, 1120... 

C7H1iCl2NOPtS, trans-Dichloro(dimethyl sulfoxide)(pyridine)platinum-... 

CbHi2Ni3Sg, Tris-M"(dithioacetato)-M3 (trithio-o-acetato)-triangulo-trinickelUl) (form II), 41B, 1148 C8Hi2Pt2Sef Tetrakis(dithioacetato)diplatinum(II)(Pt-Pt), 46B, 1206 CgHi2SbV, Tetrakis(dithioacetato)vanadium(IV), 38B, 1008 CgHi3Cl2NOPtS, cis-Dichloro(dimethyl sulfoxide)(2-picoline)platinum-(II), 43B, 1386... 

Trilialophenols can be converted to poly(dihaloph.enylene oxide)s by a reaction that resembles radical-initiated displacement polymerization. In one procedure, either a copper or silver complex of the phenol is heated to produce a branched product (50). In another procedure, a catalytic quantity of an oxidizing agent and the dry sodium salt in dimethyl sulfoxide produces linear poly(2,6-dichloro-l,4-polyphenylene oxide) (51). The polymer can also be prepared by direct oxidation with a copper—amine catalyst, although branching in the ortho positions is indicated by chlorine analyses (52). 

Notable examples of general synthetic procedures in Volume 47 include the synthesis of aromatic aldehydes (from dichloro-methyl methyl ether), aliphatic aldehydes (from alkyl halides and trimethylamine oxide and by oxidation of alcohols using dimethyl sulfoxide, dicyclohexylcarbodiimide, and pyridinum trifluoro-acetate the latter method is particularly useful since the conditions are so mild), carbethoxycycloalkanones (from sodium hydride, diethyl carbonate, and the cycloalkanone), m-dialkylbenzenes (from the />-isomer by isomerization with hydrogen fluoride and boron trifluoride), and the deamination of amines (by conversion to the nitrosoamide and thermolysis to the ester). Other general methods are represented by the synthesis of 1 J-difluoroolefins (from sodium chlorodifluoroacetate, triphenyl phosphine, and an aldehyde or ketone), the nitration of aromatic rings (with ni-tronium tetrafluoroborate), the reductive methylation of aromatic nitro compounds (with formaldehyde and hydrogen), the synthesis of dialkyl ketones (from carboxylic acids and iron powder), and the preparation of 1-substituted cyclopropanols (from the condensation of a 1,3-dichloro-2-propanol derivative and ethyl-... 

Starting from l.l-dichloro-7b-ethoxy-2-methyl-1,1 a,2,7-tetrahydrobenzo[/)]cyclopropa[prepared from the corresponding benzothiopyran by addition of dichlorocarbene, the three 1-benzothiepins 6a-c are formed upon treatment with strong bases, i.e. sodium methoxide or ethoxide in dimethyl sulfoxide.73 The optimal yield of each 1-benzo-thiepin compound depends on the molar equivalents of base, as follows from different ring-opening mechanisms. 

Inhot dimethyl sulfoxide, dimethyl 3,6-dichloro-l-tosyl-l//-azepine-4,5-dicarboxylate(24) undergoes ring contraction to dimethyl 3,6-dichloro-4-(tosylamino)phthalate (25).23... 

A mixture of the (highly activated) dichloro compound with potassium fluoride in the solvent was heated to reflux to effect replacement of chlorine by fluorine. The reaction accelerated out of control and exploded, leaving much carbonised residue. Analogous reactions had been effected uneventfully on many previous occasions. See Dimethyl sulfoxide Acyl halides, etc. 

See 1,5-Dichloro-2,4-dinitrobenzene Dimethyl sulfoxide, etc. See other haloaryl compounds, polynitroaryl compounds... 

Aluminium chloride, Nitrobenzene, 0062 Ammonium hydrogen sulfite, 4545 Benzyltriethylammonium permanganate, 3617 Bis(4-hydroxyphenyl) sulfone, 3497 2-Chloro-5-nitrobenzenesulfonic acid, 2144 1,3 -Dichloro-5,5-dimethyl-2,4-imidazolidindione, 1865 f Dimethyl sulfoxide, 0921... 

Dichloro-I, 2,3,4-tetramethyl-CYCLOBUTENE, 46, 34 o,a-Dichlorotoluene, condensation with ethyl cyanoacetate, 48, 54 Dicyclohexylcarbodiimide in oxidation of cholane-24-ol with dimethyl sulfoxide and pyridinium trifluor-oacetate, 47, 25... 

Further improvements in dehalogenation selectivity and yields can be achieved by using dipolar aprotic solvents. Dimethylformamide has mostly been used for this purpose,18,56,84 97 although dimethyl sulfoxide,98,99 especially when combined with sonication at room temperature (vide infra), deserves attention in particular cases.100,101 Other polar and dipolar aprotic solvents have also been used, namely, acetone,4 butan-2-one,4 acetonitrile,102 acetic anhydride,103104 ethyl acetate,61 tetrahydrothiophene 1,1-dioxide (sulfolane)105 and hexamethyl-phosphoric triamide,106 but no details were reported on their advantages over dimelhylform-amide or dimethyl sulfoxide. Better performance of dipolar aprotic solvents, such as dimethyl-formamide, over other solvents has been demonstrated in the recent comparison of the dehalogenation of 4,5-dichloro-4,5,5-trifluoropentan-l-ol (4) with zinc in various solvents.90... 

Dichloro-5,5-dimethyl-2,4-imidazolidindione, 1859 f Dimethyl sulfoxide, 0917 f Methyl acrylate, 1526 iV-Methyl-iV-nitrosourea, 0871 Nitric acid, 2-Aminothiazole, Sulfuric acid, 4430... 

Fluorination of 2,3,5-trichloropyridine with KF and CsF in an ionic liquid afforded 3,5-dichloro-2-fluoropyridine and 5-chloro-2,3-difluoropyridine in good yield <2004SC4301>. Spray-dried KF in hot dimethyl sulfoxide (DMSO) containing a small amount of tetramethylammonium chloride is effective for the displacement of chlorine by fluorine in certain polyhalopyridines <2005CEJ1903>. The conversion of several chloropyridines to their fluoro derivatives has been carried out at room temperature using anhydrous TBAF in DMSO <2006AGE2720> or KF in sulfolane <2002BML411>. 

In a two-phase system similar to that used by Price, Stamatoff (29) obtained from 2,6-dichloro-4-bromophenol a branched polymer having approximately the statistical ratio of ortho and para ether linkages. When the reaction was carried out using the anhydrous salt of the phenol in the presence of highly polar aprotic solvents, such as dimethyl sulfoxide, the product was the linear poly(2,6-dichlorophenylene oxide) (Reaction 23). 

AD-mix-P 9-BBN Bn Boc Bz BOM CDI m-CPBA CSA Cy DBU DDQ DEAD DIAD DIBAL-H DIPT DME DMF DMAP DMSO EDC HMPA HOBT KHMDS LDA MEM MOM MoOPH NaHMDS NBS NMM NMO Piv PMB Reagent for Sharpless asymmetric dihydroxylation 9-Borabicyclo[3.3.1 ]nonyl Benzyl t-Butoxy carbonyl Benzoyl B enzyloxy methyl Carbonyldiimidazole m-Chloroperoxybenzoic acid Camphorsulfonic acid Cyclohexyl 1,8 -Diazabicy clo[5.4.0] undec-7-ene 2,3 -Dichloro-5,6-dicyano-p-benzoquinone Diethyl azodicarboxylate Diisopropyl azodicarboxylate Diisobutylaluminum hydride Diisopropyl tartrate Dimethoxyethane A,N-Dimethylformamide 4-Dimethylaminopyridine Dimethyl sulfoxide N-(3-Dimethylaminopropyl)-A -ethylcarbodiimide Hexamethylphosphoramide 1 -Hydroxybenzotriazole Potassium hexamethyldisilazane Lithium diisopropylamide Methoxyethoxymethyl Methoxymethyl Oxidodiperoxymolybdenum(pyridine)(hexamethylphophoramide) Sodium hexamethyldisilazane N - Bromosuccinimide A-Methylmorpholine A-Methylmorpholine A-oxide Pivaloyl /j-Methoxybenzyl... 

DBPO DBU DCC DDQ DEAD DET DIBAL-H DIPT DMAP DMB DME DMF DMPU DMSO EDDA Eu(dppm)3 Eu(fod)3 dibenzoyl peroxide 1.8- diazabicyclo [ 5.4.0] undec-7-ene dicyclohexylcarbodiimide 2.3- dichloro-5,6-dicyano-l,4-benzoquinone diethyl azodicarboxylate diethyl tartrate diisobutylaluminium hydride diisopropyl tartrate iMM-dimethylaminopyridine 3.4- dimethoxybenzyl 1.2- dimethoxyethane dimethylformamide 1.3- dimethyl-3,4,5,6-tetrahydro-2(lH)pyrimidinone dimethyl sulfoxide ethylene diammonium diacetate di(perfluoro-2-propoxypropionyl)methanato europium 6.6.7.7.8.8.8- heptafluoro-2,2-dimethyl-3,5-octanedionato... 

Dichloro(l,5-cyclooctadiene)platinum(II) is a white, air-stable solid. The compound is slightly soluble in solvents such as chloroform, acetic acid, sulfolane (tetrahydrothiophene 1,1-dioxide), and nitromethane. It decomposes slowly upon dissolution in dimethyl sulfoxide. The p.m.r. spectrum of the compound in chloroform shows resonances at 4.38r, /pt H = 65 Hz., for the olefinic protons and 7.29-r for the methylene protons. The infrared spectrum in Nujol has strong absorption maxima at 1334, 1179, 1009, 871, 834, and 782 cm.-1. 

Dichloro(ethylenediamine)palladium(II) is formed as yellow needles. (2,2 -Bipyridine)dichloropalladium(II) is produced as a light yellow microcrystalline solid that can be obtained as larger crystals by careful recrystallization from hot, dilute HC1 solutions. Both compounds are insoluble in cold water, but are moderately soluble in hot water. The compounds dissolve in 1 M sodium hydroxide with reaction. In general the compounds are not soluble in organic solvents however, both complexes can be dissolved in dimethyl sulfoxide and A>Y-di met hy If or mami de. 

Ac, acetyl AIBN, azobis(isobutanonitrile) All, allyl AR, aryl Bn, benzyl f-BOC, ferf-butoxycarbonyl Bu, Butyl Bz, benzoyl CAN, ceric ammonium nitrate Cbz, benzyloxycarbonyl m-CPBA, m-chloroperoxybenzoic acid DAST, diethylaminosulfur trifluoride DBU, l,8-diazabicyclo[5.4.0]undec-7-ene DCC, /V. /V - d i eye I oh e x y I c ar bo -diimide DCM, dichloromethyl DCMME, dichloromethyl methyl ether DDQ, 2,3-dichloro-5,6-dicyano-l,4-benzoquinone DEAD, diethyl azodicarboxylate l-(+)-DET, L-(+)-diethyl tartrate l-DIPT, L-diisopropyl tartrate d-DIPT, D-diisopropyl tartrate DMAP, 4-dimethylaminopyridine DME, 1,2-dimethoxyethane DMF, /V./V-dimethylformamide DMP, 2,2-dimethoxypropane Et, ethyl Im, imidazole KHMDS, potassium hexamethyldisilazane Me, methyl Me2SO, dimethyl sulfoxide MOM, methoxymethyl MOMC1, methoxymethyl chloride Ms, methylsulfonyl MS, molecular sieves NBS, N-bromosuccinimide NIS, /V-iodosuccinimide NMO, /V-methylmorpho-line N-oxide PCC, pyridinium chlorochromate Ph, phenyl PMB, / -methoxvbenzyl PPTs, pyridiniump-toluenesulfonate i-Pr, isopropyl Py, pyridine rt, room temperature TBAF, tetrabutylammonium fluoride TBS, ferf-butyl dimethylsilyl TBDMSC1, f-butylchlorodimethylsilane Tf, trifhioromethylsulfonyl Tf20, trifluoromethylsulfonic anhydride TFA, trifluoroacetic acid THF, tetrahydrofuran TMS, trimethylsilyl TPAP, tetra-n-propylammonium perruthenate / -TsOH. / -toluenesulfonic acid... 

For example, the synjanti product ratio of the base-promoted dehydrochlorination of mes o-3,4-dichloro-2,2,5,5-tetramethylhexane with potassium t-butoxide to give (Z)- and ( )-3-chloro-2,2,5,5-tetramethyl-3-hexene changes from 92 8 in tetrahy-drofuran (ej. = 7.6) and 86 14 in t-butanol (er = 12.5) to 7 93 in dimethyl sulfoxide (fir = 46.5) [694]. 

The cobalt(III) complex [Co(2,3-Me2[14]-l,3-diene-l,4,8,l l-N4)Br2] Br is six-coordinate and diamagnetic. Analysis of the visible spectrum (absorptions occur near 15.8 and 26.2 kK) leads to a value for Dq of 2630 cm" . The NMR spectrum in dimethyl sulfoxide shows a methyl singlet at 3.32 ppm. The infrared spectrum is very similar to that given for the nickel(II) complexes. A wide variety of cobalt(lll) complexes has been prepared by metathetical reactions on the dibromo and dichloro complexes. The imine functions can be hydrogenated, producing cobalt(III) complexes of 2,3-Me2 [14] ane-1,4,8,11-N4 or 2,3-Me2-[14]-l-ene-l,4,8,ll-N4. ... 

Irradiation at 350 nm of 1,1-dibromocyclopropanes dissolved in liquid ammonia or dimethyl sulfoxide in the presence of sodium benzenesulfanate leads to l,l-bis(phenylsulfanyl)cyclo-propanes. The yields are in all cases below 50% which is due to both decomposition of the product on longer irradiation and formation of significant amounts of cyclopropyl phenyl sulfide. Most 1,1-dichlorocyclopropanes are unreactive, and no reaction occurs in the presence of oxygen, di- erf-butyl nitroxide and 1,3-dinitrobenzene, which supports the notion that the reaction is a radical process. The cleanest reaction took place during irradiation of 2,2-dichloro-1 -methylcyclopropanecarbonitrile, which gave no sulfide, little unreacted starting material, and 1-methyl-2,2-bis(phenylsulfanyl)cyclopropanecarbonitrile (4) in 47% yield. 

Treatment of l,l-dichloro-la,9b-dihydrocyclopropa[/]phenanthfene with an excess of potassium tert-butoxide and methanethiol in dimethyl sulfoxide gave 1 a,9b-bis(methylsulfanyl)-l a,9b-dihydrocyclopropa[/]phenanthrene (3) in greater than 80% yield.The reaction conceivably involves cyclopropene intermediates 1 and 2 (cf ref 725), which are both trapped by mercaptide. This mechanism is supported by the fact that cnr/o-l-chloro-la-methylsulfanyl-la,9b-dihydrocyclopropa[/]phenanthrene (4) was isolated in good yield (68%) when the dichloride was reacted with 1 equivalent of potassium rert-butoxide and a deficit of methanethiol. l,l-Dichloro-la-methyl-la,9b-dihydrocyclopropa[/]phenanthrene reacts similarly under the same conditions to give cn[Pg.1409]

It is also possible to obtain methylenecydopropanes by monodehydrochlorination of compounds other than 1-chloro-l-methylcyclopropanes. For example, inverse addition of potassium terf-butoxide in dimethyl sulfoxide at 25°C to l,l-dichloro-2,2,3-trimethylcyclopropane (20) gave a 33% yield of 2-chloro-l,l-dimethyl-3-methylenecyclopropane (21) along with a 30% yield of ring-opened product 22. This is one case in which the usual double dehydrochlorination of 1,1-dichlorocyclopropanes (see Section 5.2.2.1.2.3.) is blocked and a single elimination occurs instead. Another example is the reaction of l-chloro-2,3-dimethylcyclopropane (23) with potassium tcr/-butoxide in dimethyl sulfoxide at 80-90 to give l-methyl-2-methyl-enecyclopropane (24) in 84% yield (see also below and Sections 5.2.2.1.1.1.2. and 5.2.2.1.1.2.). 

---