Chloro-2-methyl-4,4,6-triphenyl

A detailed six-step procedure for the synthesis of 2-chloro-2-methyl-4,4,6-triphenyl-1,3,5,22 42 -triazadiphosphinine (246) by thermal cyclocondensation of benzamidinium chloride (244) with the diphosphazene (245) (Equation (13)) under 10 torr vacuum at 140-150°C has been described <89IS24>. 

Use of the more reactive tetrabromosilane leads to the bis- and tris-(chloro-methyl) compounds without the necessity for a catalyst.383 Diazomethane reacts with trichlorosilane or trichloro(methyl)silane in the presence of copper powder to yield, respectively, dichloro(chloromethyl)silane385 386 and di-chloro(chloromethyl)(methyl)silane,383 but no chloromethyl derivative can be obtained in this way from chlorosilanes carrying three organic groups, such as chloro-(trimethyl), -(triethyl)-, and -(triphenyl)-silane. 

By this method (Z)-monounsaturated fatty acids and esters could be obtained with an ( )-isomer content of less than 10% this stereoselectivity being however inferior to that of the commonly used acetylenic approach 55,56). However, the salt-free techniques used today in Wittig reactions allow (Z)-alkenoic acids to be synthesized with less than 2% of the ( )-isomers. Thus, Bestmann et al. prepared methyl and ethyl esters of (Z)-4,5,6,7,8,9,ll- and 13-alkenoic acids of different chain lengths 35,57 62), which served as intermediates in the synthesis of insect pheromones, both by reaction of co-alkoxycarbonyl-substituted alkyl-triphenyl-phosphonium salts with simple alkanals and of co-formylalkanoic esters with alkylidenephosphoranes. As the starting material for the synthesis of -substituted alkyl-phosphonium salts co-chloro- and -bromocarboxylic esters were used. The corresponding -substituted aldehydes can usually be obtained by ozone cleavage of suitable olefin derivatives or by oxidation of alkohols 57,58). 

Anodic oxidation of formazanes in MeCN-TEAP at a platinum anode produces tetrazolium salts in good yield [120, 121]. The ring closure probably takes place through the dication. A similar anodic coupling is the oxidation of 2-acetylpyridine phenyl-hydrazone to 3-methyl-l-phenyl-8-azaindazolium perchlorate [41], of benzilmonoxime phenylhydrazone to 2,4,5-triphenyl-1,2,3-triazole-1-oxide, and of 3-hydroxyiminomethyl-eneamino-6-chloropyridazine to 6-chloro-5-triazole[l,5-Z>]pyridazine-3-oxide [74, 122]. 

Chloro-phenyl)-l, 2,7-triphenyl- 3055 5-(4-Methyl-phenyl)-l, 2,7-triphenyl- 3055... 

The first representative, 3,4,5-triphenyl-1,2-thiaphosphole (14) was observed as side product and isolated in low yields (1 % or below) along with 3,5-diphenyl-1,2,4-thiadiphosphole from the reaction of l,3,4-oxathiazol-2-ones (13), Ar = 2-MeC6H4, 2,6-Cl2C6H3, and a l-chloro-2-trimethylsilyl phos-phaalkene (Equation (3)) <88TL4535>. The corresponding reaction of the methyl derivative (15)... 

Reactions of Isoxazoles. The kinetics of the isoxazole azirine rearrangement (336) -> (337) and those of the isoxazole oxazole transformation (338) (339) have been determinedPalladium(II) chloride-triphenyl-phosphine catalyses the cross-coupling of 4-iodo-3,5-dimethylisoxazole with styrene to yield the trans- compound (340). 3,5-Dimethylisoxazole can be lithiated in two stages, first at the 5-methyl group and then at the 3-methyl group. Isoxazoles add hypochlorous acid to form 4-chloro-2,3-dihydro-... 

One might expect that a phosphorus reagent having for R an aryl group activated for bimolecular nucleophilic substitution (68) by electron- withdrawing substituents might participate in a Michaelis-Arbuzov reaction. Kamai and Koshkina (159), who prepared a number of chloro-and nitro-substituted derivatives of triphenyl phosphite, found this to be the case for both ortho and para isomers of tris(monochlorophenyl) phosphite, which reacted with alkyl halides to furnish phosphonates. On the other hand, tris(2,4,6-trichlorophenyl) phosphite and tris(2,4-dichlorophenyl) phosphite (155) gave only complexes with methyl iodide however, lower reaction temperatures were employed. 

The infrared spectra of some other types of highly chlorinated aromatic compounds (a//-quasiperchloro compounds, perchloro-di- and triphenyl-methyl radicals, fused polycyclic aromatic chlorocarbons, aromatic chloro-carbon ions) have also been recorded and reviewed (Ballester et al., 1978c). 

Methane, bromo-, 55,63 Methane, (4-fert-butylphenyl)-phenyl-[Methane, 4-(l,l-dimethylethyl)-phenyl-phenyl-1,55,11 Methane, iodo-, 55, 3 Methane, iodo-, hazard note, 55,134 Methane, (4-isopropylphenyl)-phenyl- [Methane, (4-( l-methylethyl)phenyl>phen-yl-l,55,ll Methane, nitio-, 55, 78 Methane, triphenyl-, 55,11 Methanesulfonyl chloride, 55, 116, 120 Methyl chloride, diphenyl- [Methane, chlo-rodiphenyl-],55, 94 Methyl ether, chloromethyl- [Methane, chloro-methoxy-], 55,94... 

A BASF patent [30] describes the transformation of 81 into 4-chloro-2-methylbut-2-enal (88), which is an ideal precursor for the preparation of (3-methyl-4-oxobut-2-enyl)-triphenyl-phosphonium chloride (89). The phosphonium salt 89 is usually acetalized before being used in Wittig condensations [19,31]. Acetylation of 88 with potassium acetate in anhydrous ethanol furnished the acetoxyaldehyde 73 in high yield [32]. 

Acyclic Alditols. - Chain-shortening of aldoses to the next lower alditol by decarbonylation has been accomplished by heating in N-methyl-2-pyrrolidinone in the presence of chloro(triphenyl-phosphine)rhodium... 

Thionyl chloride added during 15 min. to a soln. of 4a-methyl-l,3,9-triphenyl-4aH-fluorene in benzene and dry dimethyl sulfoxide, stirring continued 3 hrs. -> 4-chloro-4a-methyl-l,3,9-triphenyl-4aH-fluorene. Y 94%.—POCI3 may be used in place of SOGlg. F. electrophilic substitutions of the above strongly basic hydrocarbon H. W. Moore and H. R. Snyder, J. Org. Chem. 29, 97 (1964). 

In an extension of these studies, a new synthesis of indole derivatives was reported (Mori and Ban, 1976a) from 2-chloro-N-methyl-lV-allylaniline (XLll) by refluxing in ether for several hours with tetrakis(triphenyl-phosphine)nickel [Ni(PPh3)4]. The latter was prepared in situ to prevent deallylation. After oxygen was bubbled through the solution to convert PPhs into O <— PPhs for easy handling, the 1,3-dimethyl indole (XLIII) was obtained in a yield of 45.6%. 

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