2- Chloro-p-xylene

Hartwig [9] et al. developed a novel ferrocene-based dialkyl-phosphine-ligand for this arylation 2-methoxy-4-methyl-phenol is arylated with 2-chloro-p-xylene in 81% yield [eq. (g)]. 

Furthermore, in 1995, Sony Corporation found that halogen-containing alkoxy-benzenes, such as 2-chloro-p-xylene (101), 4-chloroanisole(102), 2,4-difluoroanisole (103), 3,5-difluoroanisole (104), and 2,6-difluoroanisole (105) can be used as additives in small qnantities [113]. 

A 250-ml., three-necked, round-bottomed flask is equipped with a 50-ml. pressure-equalizing dropping funnel capped by a rubber septum, an efficient reflux condenser connected to a nitrogen inlet, and a magnetic stirrer (Note 1). The flask is charged with 7.02 g. (0.05 mole) of a-chloro-p-xylene (Note 2) and 45.6 g. (0.63 mole) of ethyl vinyl ether (Note 3). A solution of 7.06 g. (0.05 mole) of... 

The reaction of 7-chloro-p-xylene with potassium tert-butoxide in p-xylene in the presence of stable N-oxy biradicals such as 2,2,6,6-tetramethylpiperidinoxy-4-spiro-2 -(r,3 -dioxane)-5 -spiro-5"-(r, 3"-dioxane)-2"-spiro-4 -(2 ",2", 6", 6 "-tetramethyl piperidinoxy) gives the corresponding copolymer 36 indicating the formation of QM as a reaction intermediate. 

Chloroethanol, 254 j0-Chlorophenetole, 253 a-Chloro-p-xylene, 142 trani-Cinnamic acid, 238 Citric acid, 274 Crotonic acid, 241 1,2-Dichloropropane, 272 Diethyl succinate, 252 A,A-Dimethylformamide, 320... 

Beller has demonstrated that a new bulky, electron-rich trialkylphosphine, di(l-adamantyl)-n-butylphosphine, w-BuPAd2, can afford excellent TONs in palladium-catalyzed Suzuki reactions of aryl chlorides [34]. For the coupling of 4-chlorotoluene, this phosphine achieves a TON of 17 400 (0.005 mol% Pd, 87% yield) (Equation 2.19), compared with a TON of 9200 with commercially available P(t-Bu)3 (0.01 mol% Pd, 92% yield). High TONs (>10000) can also be obtained with challenging aryl chlorides, such as 2-chloro-m-xylene and 4-chloroanisole. 

Chloroethanol, 396, 462 /1-Chlorophenetole, 395 a-Chloro-p-xylene, 256 trans-Cim 3imc acid, 278, 398 Crotonic acid, 400... 

Chloroethanol, 276, 334 /J-Chlorophenetole, 275 a-Chloro-p-xylene, 146 fran,y-Cinnamic acid, 278 Citric acid, 257 Crotonic acid, 280 Diethyl succinate, 274 iV,iV-Dimethylformamide, 347 2,4-Dinitroanisole, 291 Ethanol, 331, 332... 

Benzoic m-Toluic (Benzoic acid, 3-methyl-] p-Toluic [Benzoic acid, 4-methyl-J 3,5-Dimcthylbcnzoic [Benzoic acid, 3,5-dimcthyl-] p-Chlorobenzoic [Benzoic acid, 4-chloro-] p-Bromobenzoic [Benzoic acid, 4-bromo-J Phthalic [ 1,2-Bcnzcncdicarboxylic acid] Toluene [Benzene, methyl-] (78) m-Xylene [Benzene, 1,3-dimethyl-] (82) />-Xylene [Benzene, 1,4-dimethyl-] (74) Mesitylene [Benzene, 1,3,5-trimethyl-] (82) p-Chlorotolueno [Benzene, l-ehloro-4-methyl-] (94) p-Bromotolucnc [Benzene, l-bromo-4-methyl-] (94) o-Xylene [Benzene, 1,2-dimethyl-] (64)... 

Stock and Baker2 5 9 measured the relative rates of chlorination of a number of halogenated aromatics in acetic acid containing 20.8 M H20 and 1.2 M HC1 at 25 °C and the values of the second-order rate coefficients (103Ar2) are as follows p-xylene (11,450), benzene (4.98), fluorobenzene (3.68), chlorobenzene (0.489), bromobenzene (0.362), 2-chlorotoluene (3.43), 3-chlorotoluene (191), 4-chloro-toluene (2.47), 4-fluorotoluene (9.70), 4-bromotoluene (2.47). Increasing the concentration of the aromatic, however, caused, in some cases, a decrease in the rate coefficients thus an increase in the concentration of chlorobenzene from 0.1 M to 0.2 M caused a 20 % decrease in rate coefficient, whereas with 4-chloro-and 4-bromo-toluene, no such change was observed. 

The method described for the preparation of N-methyl-2-pyrrolidinethione is very similar to that of Peak and Stansfield 2 for the preparation of 4-thioacetylmorpholine. N-Methyl-2-pyrrolidinethione has also been prepared by the reaction of 2-chloro-N-methyl-A1-pyrrolinium chloride with hydrogen sulfide [yield 83% b.p. 144-145° (15 mm.)]3 and by heating N-methyl-2-pyrrolidinone with 2 equivalents of phosphorus pentasulfide in xylene [yield not reported b.p. 125-132° (10 mm.)].4 General procedures for the preparation of N,N-disubstituted thioamides have been reviewed.5, 6... 

Nuclear halogen often makes oxidation more difficult it protects alkyl groups against attack. Thus oxidation of 4-chloro-m-xylene and 2,5-dibromo-p-xylene by chromic acid proceeds only as far as 4-chloro-w-toluic and 2,5-dibromo-p-toluic acid, respectively 401 the latter requires alkaline permanganate for conversion into the dibromoterephthalic acid.402... 

CAS 88-04-0 EINECS/ELINCS 201-793-8 Synonyms Benzytol 4-Chloro-3,5-dimethylphenol 2-Chloro-5-hydroxy-m-xylene 4-Chloro-3,5-xylenol p-Chloro-m-xylenol Parachlorometa-xylenol PCMX... 

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