1.2- dichloro-aryl

Different amino-, alkyl-, and aryl-substituted phosphepines 7-12 and 90 were also obtained in two steps directly from binaphthyl 84 and dichloro-Ar,Ar-dialkylphosphinamines, dichloro(alkyl)phosphines, or dichloro(aryl)phosphines in 60-80% yields. This method requires initial metallation of 2,2 -dimethylbinaphthyl 84 with -BuLi and isolation of dilithio salt in the crystalline form <2004TA2621, 2003JOM(675)91, 2002TL4977>. 

Since the exocyclic sulfur is more reactive in the ambident anion than in A-4-thiazoIine-2-thione. greater nucleophilic reactivity is to be expected. Thus a large variety of thioethers were prepared in good yields starting from alkylhalides (e.g.. Scheme 38 (54, 91, 111, 166-179). lactones (54, 160), aryl halides (54, 152. 180, 181), acyl chlorides (54. 149, 182-184). halothiazoles (54, 185-190), a-haloesters (149. 152. 177. 191-194), cyanuric chloride (151). fV.N-dimethylthiocarbamoyl chloride (151, 152. 195. 196), /3-chloroethyl ester of acrylic acid (197), (3-dimethylaminoethyl chloride (152). l,4-dichloro-2-butyne (152), 1,4-dichloro-2-butene (152), and 2-chloro-propionitrile (152). A general... 

Alkyl- and aryl-pyridazines can be prepared by cross-coupling reactions between chloropyridazines and Grignard reagents in the presence of nickel-phosphine complexes as catalysts. Dichloro[l,2-bis(diphenylphosphino)propane]nickel is used for alkylation and dichloro[l,2-bis(diphenylphosphino)ethane]nickel for arylation (78CPB2550). 3-Alkynyl-pyridazines and their A-oxides are prepared from 3-chloropyridazines and their A-oxides and alkynes using a Pd(PPh3)Cl2-Cu complex and triethylamine (78H(9)1397). 

The 3- and4-arylfuran-2(5//)-ones 152 and 153 (Ar = Ph, 2-Me—COO—QH4, 3-CF3—C6H4, 2-Me—C6H4, 2-thienyl) were conveniently obtained by coupling of 3- and4-stannylfuranones 151 and 134 with aryl iodides using dichloro-bis(triphe-nylphosphine)Pd(II) as catalyst and toluene as the solvent [96JCS(P1)1913]. 

The NH2 groups can be diazotized and reduced in the presence of thiosulphates and different metal ions. The effect of some metal ions, namely Fe ", Sn, Cu +, and Co on the graft yield of cotton modified with aryl diazonium groups via its reaction with 2,4-dichloro-6-(p-nitroaniline)-5-triazine in the presence of alkali and followed by reduction of nitro group was studied [4]. 

The reaction given here has been described before as a general reaction,2 and there can be a wide variety of alkyl, aryl, and halo substituents on the diene and phosphorus. Dibromophosphines are appreciably more reactive than dichlorophosphincs. If a free-radical catalyst is used instead of an inhibitor, the copolymers can be made in good yield.3 The 1,4-addition of dichloro-phosphines to 1,3-dienes is of theoretical interest because of its analogy to the well-known 1,4-addition of sulfur dioxide to 1,3-dienes. 

Monoalkylation products, 3-aryl-1,1 -dichloro-1 -silabutanes, were obtained from the alkylation of aromatic compounds with I in the presence of aluminum chloride catalyst in good isolated yields (60-80%) along with small amounts of higher alkylation products. Dialkylation products were obtained in yields ranging from 2 to 8% when a 5-fold excess of the aromatic compounds with respect to 1 was used. The amount of dialkylated products can be further reduced by using a greater excess of the aromatic compounds. 

Other blockers of epithelial Cl -channels are of the aryl-amino-benzoate type or phenoxy-acetic-acid type [70]. Very few systematic surveys comparing different classes of blockers in one type of Cl -channel are available at this stage. One such study has been performed in membrane vesicles from kidney cortex [80]. In this study IAA-94 and NPPB (cf. Fig. 2) turned out to be the most potent blocker of conductive Cl -flux. In another systematic survey the Cl -conductance of the sweat duct was examined, and it was found that dichloro-DPC (Fig. 2) was the most potent inhibitor of the transepithelial Cl -conductance [90]. 

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