cas 552-45-4, 2-Methylbenzyl chloride | Articles data

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Mechanism of solvolysis of substituted benzyl chlorides in aqueous ethanol
The mechanism of solvolyses of activated ortho-, meta- and para-substituted benzyl chlorides in aqueous ethanol has been studied by using the Hammett-Brown and Yukawa-Tsuno treatments as well as by correlating logarithms of solvolysis rate constants with relative stabilities of corresponding benzyl carbocations in water calculated at the IEFPCM-M06–2X/6-311+G(3df,3pd) level of theory. Benzyl chlorides containing strong conjugative electron-donors in the para-position solvolyze by the SN1 mechanism, whereas other activated benzyl chlorides solvolyze by the SN2 mechanism via loose transition states.
Denegri, Bernard,Mati?, Mirela,Va?ko, Monika
supporting information

(2021/11/22)

Synthesis method of 3-isochromanone
The invention belongs to the technical field of synthesis of organic intermediates, and particularly relates to a synthesis method of 3-isochromanone, which comprises the following steps of: (1) synthesizing o-methyl benzyl chloride by using o-xylene as a raw material; (2) synthesizing o-methyl benzyl cyanide by taking o-methyl benzyl chloride as a raw material; (3) synthesizing sodium o-methyl phenylacetate by taking o-methyl benzyl cyanide as a raw material; (4) synthesizing o-methyl phenylacetic acid by taking sodium o-methyl phenylacetate as a raw material; (5) synthesizing 2-chloromethylphenylacetic acid by taking o-methyl phenylacetic acid as a raw material; and (6) synthesizing 3-isochromanone by taking 2-chloromethyl phenylacetic acid as a raw material. The synthesis method of 3-isochromanone has the advantages of simple reaction process, easily available raw materials, mild reaction conditions, high product yield, low production cost, high yield, high product purity, good quality, low production waste discharge amount and the like, the product purity is greater than or equal to 99.5%, the production yield is greater than or equal to 92%, and the product meets the use requirements of foreign high-end users.
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Paragraph 0033; 0042-0045; 0056-0059; 0070-0073

(2021/01/04)

NMP-mediated chlorination of aliphatic alcohols with aryl sulfonyl chloride for the synthesis of alkyl chlorides
NMP-mediated chlorination of aliphatic alcohols has been developed for the synthesis of alkyl chlorides. This facile, efficient and practical approach used simple and readily available aryl sulfonyl chlorides as the chlorination reagent for the construction of C–Cl bond in good to excellent yields with mild conditions and broad substrate scope.
Zheng, Dagui,Mao, Liu-Liang,Zhu, Xian-Hong,Zhou, An-Xi
supporting information
p. 2793 - 2800
(2018/11/06)

Formamides as Lewis Base Catalysts in SNReactions—Efficient Transformation of Alcohols into Chlorides, Amines, and Ethers
A simple formamide catalyst facilitates the efficient transformation of alcohols into alkyl chlorides with benzoyl chloride as the sole reagent. These nucleophilic substitutions proceed through iminium-activated alcohols as intermediates. The novel method, which can be even performed under solvent-free conditions, is distinguished by an excellent functional group tolerance, scalability (>100 g) and waste-balance (E-factor down to 2). Chiral substrates are converted with excellent levels of stereochemical inversion (99 %→≥95 % ee). In a practical one-pot procedure, the primary formed chlorides can be further transformed into amines, azides, ethers, sulfides, and nitriles. The value of the method was demonstrated in straightforward syntheses of the drugs rac-Clopidogrel and S-Fendiline.
Huy, Peter H.,Motsch, Sebastian,Kappler, Sarah M.
supporting information
p. 10145 - 10149
(2016/08/16)

Improved Halogenation of Methyl Aromatics and Methyl Heteroaromatics: Unexpected Reactivity of Tetrahalogeno-diphenylglycolurils
1,3,4,6-Tetrachloro (TCDGU) and 1,3,4,6-tetrabromo-3α,6α-diphenylglycolurils smooth halogen oxidizers have been exploited in a new direction as reagents for free radical substitution toward some N-halosuccinimide nonreactive bis-heterocycles. An unexpected selectivity and reactivity were observed with methyl benzenes, methyl heterocycles, and methyl-bis-heterocycles of interest. A chemometric study has been performed to optimize five independent factors of the chlorination reaction with TCDGU. The predictive model was established either for the halogenation conversion and the ratio of monochlorination.
Moretti, Florian,Poisson, Guillaume,Marsura, Alain
p. 173 - 183
(2016/05/19)

Iron catalyzed halogenation of benzylic aldehydes and ketones
A simple and efficient iron-catalyzed method for chlorination of aromatic carbonyl compounds is reported. By using 4-10 mol% Fe(iii) oxo acetate catalyst, prepared by solid state atmospheric oxidation of Fe(ii) acetate, in combination with triethylsilane and chlorotrimethylsilane, hydrosilylation of benzylic carbonyl compounds with subsequent chlorination is achieved within a few hours at room temperature. This new method is mild and rapid compared to the conventional two step approach involving reduction and chlorination reactions in separate stages. Development of synthetic methodology is also supplemented here by kinetic investigation of the reaction mechanism, which supports the tentative mechanisms suggested previously for similar reactions. This journal is
Savela, Risto,W?rn?, Johan,Murzin, Dmitry Yu.,Leino, Reko
p. 2406 - 2417
(2015/04/14)

An experimental and theoretical study on imidazolium-based ionic liquid promoted chloromethylation of aromatic hydrocarbons
The chloromethylation of aromatic hydrocarbons proceeded efficiently using the reusable imidazolium-based ionic liquid as promoter. Mild reaction conditions, enhanced rates, improved yields, recyclability of ionic liquids, and reagents' reactivity which is different from that in conventional organic solvents are the remarkable features observed in ionic liquids. The ionic liquids were recycled in three subsequent runs with no decrease in activity. In addition, the results of calculations with the Gaussian 98 suite of program are in good accordance with the experimental outcomes.
Wang, Yun,Xi, Yanli
p. 2196 - 2199
(2014/03/21)

Efficient organic transformations mediated by ZrOCl28H 2O in Water
Operationally simple and environmentally benign methods for some organic transformations comprising reductive coupling of sulfonyl chlorides, chemoselective deoxygenation of sulfoxides, and halogenation of alcohols mediated by ZrOCl28H2O/MX in water have been developed.
Jafarpour, Maasoumeh,Rezaeifard, Abdolreza,Heidari, Mahdieh
experimental part
p. 1470 - 1482
(2011/10/05)

An inexpensive and convenient procedure for chloromethylation of aromatic hydrocarbons by phase transfer catalysis in aqueous media
Reaction of aromatic hydrocarbons catalyzed by a novel catalytic system consisting of zinc chloride, acetic acid, sulfuric acid and PEG-800 in aqueous media under PTC conditions results in chloromethylation in good to excellent yield.
Hu, Yu Lin,Lu, Ming,Ge, Qiang,Wang, Peng Cheng,Zhang, Sheng Bin,Lu, Ting Ting
experimental part
p. 97 - 102
(2010/08/05)

A novel synthesis of tolunitriles by selective ammoxidation
A new approach to synthesize tolunitriles is reported. Tolunitriles can be prepared by selective ammoxidation of methylbenzyl chlorides prepared by chloromethylation of toluene. The total yields can reach 83% and the selectivity of tolunitriles is almost 100%. This approach provides a new path for preparing alkylbenzonitriles and other aromatic nitriles.
Xie, Guangyong,Zhang, Aiqing,Huang, Chi
experimental part
p. 969 - 973
(2011/12/15)

Microwave assisted solid additive effects in simple dry chlorination reactions with n-chlorosuccinimide
Solid additives participate in the dry microwave assisted chlorination reaction of N-chlorosuccinimide with the xylenes affecting both yields and chemoselectivities. Total yields can be increased up to nine times for simple alkylaromatics and chemoselectivities can be altered according to the desired ring or α-side chlorination product by choosing the appropriate additive. We believe that in these reactions the solid additives play a very important role by increasing yields and affecting chemoselectivities, as well as behaving as microwave energy absorbers that consequently aid the transfer of heat to the active reagents.
Bucos, Madalina,Villalonga-Barber, Carolina,Micha-Screttas, Maria,Steele, Barry R.,Screttas, Constantinos G.,Heropoulos, Georgios A.
experimental part
p. 2061 - 2065
(2010/04/26)

Regiospecific chlorination of xylenes using K-10 montmorrillonite clay
Regiospecific chlorination of xylenes has been developed by employing NCS as a reagent and K-10 montmorrillonite clay as a solid support. Copyright Taylor & Francis Group, LLC.
Thirumamagal,Narayanasamy, Sureshbabu,Venkatesan
scheme or table
p. 2820 - 2825
(2009/05/07)

[emim]BF4-promoted chloromethylation of aromatic hydrocarbons
The chloromethylation of aromatic hydrocarbons proceeded efficiently using the reusable ionic liquid [emim]BF4 as promoter. The reactions were completed in 5 h at 70°C with good yields and easy workup. Copyright Taylor & Francis Group, LLC.
Wang, Yun,Shang, Zhi-Cai,Wu, Tian-Xing
p. 3053 - 3059
(2007/10/03)

PROCESS FOR HALOGENATION OF BENZENE AND BENZENE DERIVATIVES
In a process of halogenation of benzene or benzene derivatives, di-substituted halobenzene derivatives having para-aromatic compounds or tri-substituted halobenzene derivatives having 1,2,4-substituted aromatic compounds are selectively produced. In halogenation of benzene or benzene derivatives, a fluorine-containing zeolite catalyst such as L-type zeolite, or a zeolite catalyst having the crystal size of at most 100 nm is used. The reaction is preferably effected in the presence of a solvent, and the solvent is preferably a halogenated compound.
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Page/Page column 23-24

(2008/06/13)

Efficient synthesis of tolunitriles by selective ammoxidation
Tolunitriles have been efficiently synthesized by selective ammoxidation of methylbenzyl chlorides prepared with chlorination of xylenes. In comparison with ammoxidation of xylenes themselves, the reaction temperature of ammoxidation of methylbenzyl chlorides has been lowered more than 100°C and the selectivity forming mono-nitriles is almost 100%.
Xie, Guangyong,Zheng, Qiong,Huang, Chi,Chen, Yuanyin
p. 1103 - 1107
(2007/10/03)

Process for producing isochromanones and intermediates thereof
(1) Methods for producing isochromanone compounds from o-xylene compounds as starting compounds through α-halogeno-o-xylene derivatives, α-cyano-o-xylene derivatives, and α-halogeno-α′-cyano-o-xylene derivatives, and (2) methods for producing isochromanone compounds from o-xylene compounds as starting compounds through α,α′-dihalogeno-o-xylene derivatives, α,α′-dihydroxy-o-xylene derivatives, α-halogeno-α′-hydroxy-o-xylene derivatives and α-cyano-α′-hydroxy-o-xylene derivatives, and methods for producing these intermediate compounds.
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Example 14

(2008/06/13)

EPR investigation of persistent radicals produced from the photolysis of dibenzyl ketones adsorbed on ZSM-5 zeolites
Photolysis of ketones (1, 1-oMe, 2, 2-oMe, 3, and 4) adsorbed on ZSM-5 zeolites produces persistent carbon-centered radicals that can be readily observed by conventional steady-state EPR spectroscopy. The radicals are persistent for time periods of seconds to many hours depending on the supramolecular structure of the initial radical@zeolite complex and the diffusion and reaction dynamics of radicals produced by photolysis. The structures of the persistent radicals responsible for the observed EPR spectra are determined by a combination of alternate methods of generation of the same radical, by deuterium substitution, and by spectral simulation. A clear requirement for persistence is that the radicals produced by photolysis must either separate and diffuse from the external to the internal surface or be generated within the internal surface and separate and diffuse apart. The persistence of radicals located on the internal surface is the result of inhibition of radical-radical reactions. Radicals that are produced on the external surface and whose molecular structure prevents diffusion into the internal surface are transient because radical-radical reactions occur rapidly on the external surface. The reactions of the persistent radicals with oxygen and nitric oxide were directly studied in situ by EPR analysis. In the case of reaction with oxygen, persistent peroxy radicals are formed in high yield. The addition of nitric oxide scavenges persistent radicals and leads initially to a diamagnetic nitroso compound, which is transformed into a persistent nitroxide radical by further photolysis. The influence of variation of radical structure on transience/persistence is discussed and correlated with supramolecular structure and reactivity of the radicals and their parent ketones.
Turro, Nicholas J.,Lei, Xue-Gong,Jockusch, Steffen,Li, Wei,Liu, Zhiqiang,Abrams, Lloyd,Ottaviani, M. Francesca
p. 2606 - 2618
(2007/10/03)

Interpretation of retention indices in gas chromatography for establishing structures of isomeric products of alkylarenes radical chlorination
By an example of previously uncharacterized products obtained by alkylarenes radical chlorination was demonstrated that combination of various interpretation methods applied to the retention indices (RI) in the gas chromatography on the standard nonpolar phases (comparison of RI of products and initial compounds, characteristics of succession of the chromatographic elution of the structural isomers with the use of estimation of molecular dynamic parameters, application of the additive schemes to RI calculation, and using of structural analogy CH3?Cl for testing the results obtained) permitted unambiguous identification of the structure even without data of mass spectrometry.
Zenkevich
p. 270 - 280
(2007/10/03)

An unexpected product in the photooxygenation of a cyclic enol ether
The photooxygenation product of a cyclic enol ether conjugated with an o-phenylene ring is a novel epoxy compound instead of a 1,2,4-trioxane analogue. The structure of the compound was elucidated by X-ray analysis.
Wu, Jin-Ming,Li, Ying
p. 6737 - 6739
(2007/10/03)

Electrophilic Aromatic Substitution. 13.1 Kinetics and Spectroscopy of the Chloromethylation of Benzene and Toluene with Methoxyacetyl Chloride or Chloromethyl Methyl Ether and Aluminum Chloride in Nitromethane or Tin Tetrachloride in Dichloromethane. the Methoxymethyl Cation as a Remarkably Selective Common Electrophile
Vacuum line kinetics studies have been made of the reaction in nitromethane between benzene and/or toluene, methoxyacetyl chloride (MAC), and AlCl3 to produce benzyl or xylyl chlorides, CO, and a CH3OH- AlCl3 complex. For both arenes, the rate law appears to be R = (k3/[AlCl3]0) [AlCl3]2-[MAC]. When chloromethyl methyl ether (CMME) is substituted for MAC, a similar rate law is obtained. Both chloromethylation reactions yielded similar, large kT/kB ratios (500-600) and similar product isomer distributions with low meta percentages (～0.4) which suggest CH3OCH2+ or the CH3OCH2+Al2Cl7 - ion pair as a common, remarkably selective, electrophile. The kinetics of MAC decomposition to CMME and CO in the presence of AlCl3 yielded the rate law R = k2[AlCl3]0[MAC]. Here AlCl3 is a catalyst (no CH3OH is formed), and thus the rate law is equivalent to the chloromethylation rate law. All three reactions have comparable reactivities, which is consistent with rate-determining production of the electrophile. Kinetics studies of benzene or toluene with SnCl4 and MAC or CMME in dichloromethane were also completed. With MAC and benzene the rate law is R = k3[SnCl4]0[MAC][benzene] and with toluene R = k2[SnCl4]0[MAC]. MAC decomposition, again followed by CO production, was unaffected by the presence of either aromatic and obeyed the rate law R = k2′ [SnCl4]0[MAC] where k2 ≈ k2′ Chloromethylation with CMME followed the rate law R = k3[SnCl4]0[CMME][arene] for benzene and toluene and produced a kT/kB ratio and product isomer distributions very similar to those determined with AlCl3 in nitromethane, further supporting a common electrophile. Low-temperature 13C and 119Sn FT-NMR and Raman spectroscopic studies suggest the existence of a weak 1:1 adduct between MAC and SnCl4 of the type RCXO → SnCl4, with electron donation to the metal through carboxy oxygen. Finally, an explanation is provided for the range of chloromethylation kT/kB values and product isomer percentages published in the literature.
Dehaan, Franklin P.,Djaputra, Markus,Grinstaff, Mark W.,Kaufman, Craig R.,Keithly, James C.,Kumar, Amit,Kuwayama, Mark K.,Dale Macknet,Na, Jim,Patel, Bimal R.,Pinkerton, Michael J.,Tidwell, Jeffrey H.,Villahermosa, Randy M.
p. 2694 - 2703
(2007/10/03)

Sequence of reactant combination alters the course of the Staudinger reaction of azides with acyl derivatives. Bimanes. 30
The Staudinger reaction of azides has now been followed by NMR and other spectroscopic techniques. syn-(Azidomethyl,methyl)(methyl,methyl)(bimane (1) and Ph3P form a triazaphosphadiene intermediate 2 and then the bimane P-triphenyliminophosphorane 3. The iminophosphorane reacts with an acyl chloride to yield an iminophosphonium salt 4 which then forms the oxazaphosphetane 13. The latter undergoes an electrocyclic reversion to form the phosphine oxide and the chloroimines 7E and 7Z, the last being hydrolyzed to the (acylamido)bimane 6. This set of reactions constitutes the "iminophosphorane pathway". A significant diversion of the reaction path to an (N-alkylamino)-phosphonium chloride 8 occurs through reaction of 4 with H2O present in the CDCl3 and through reaction of 3 with HCl. A different azide (α-azido-o-xylene 1b) produces the (acylamido)-o-xylene as the sole product. A less sterically hindered phosphine (tri-2-furylphosphine) reacts more slowly to form the iminophosphorane 3a from the azidobimane 1. Reaction of the bimane P-tri-2-furyliminophosphorane with acyl chloride gives only the (acylamido)bimane 6. If the acyl chloride is mixed with 1, followed by addition of the Ph3P, the triazaphosphadiene adduct 5 is formed via the triazaphosphadiene. The adduct 5 is converted rapidly into a six-membered cyclic compound 11. The latter either loses nitrogen to yield 6 via 7Z and 7E and the phosphine oxide or loses chloride 10 through a novel chloride-induced elimination reaction from its protonated form. The change in procedure thus results in a dramatic change in the reaction pathway, a reaction set that constitutes the "triazaphosphadiene adduet pathway". In the case of α-azido-o-xylene, α-chloro-o-xylene (10b) is the only product. The reactions of the azides 1 or 1b with tri-2-furylphosphine also produce chlorides as the major products accompanied by some acetamido derivatives. The nucleophile-induced reaction explains a "surprising result" (formation of ester rather than amide) reported by Sahlberg et al. (Sahlberg, C.; Jackson, A. M.; Claesson, A. Acta Chem. Scand. 1988, B42, 556-562). The intramolecular "aza-Wittig" reaction may depend on the nucleophilicity of the triazaphosphadiene. A comprehensive mechanistic scheme for the Staudinger reaction of azides is conveniently divided into the following: (A) formation of the triazaphosphadiene (Scheme 1), (B) reactions of the triazaphosphadiene (Scheme 2), and (C) reactions via the iminophosphorane (Scheme 3). Some approximate kinetic parameters are reported for some of the reactions.
Shalev, Deborah E.,Chiacchiera, Stella M.,Radkowsky, Annette E.,Kosower, Edward M.
p. 1689 - 1701
(2007/10/03)

Versatility of Zeolites as Catalysts for Ring or Side-Chain Aromatic Chlorinations by Sulfuryl Chloride
Zeolites catalyze chlorination of aromatics by sulfuryl chloride SO2Cl2.It is possible by an appropriate choice of the catalyst to effect at will, with very high selectivity, either the ring or the side-chain chlorination.Zeolite ZF520 is the choice catalyst for the former, because of its high Broensted acidity.Zeolite NaX (13X) is a fine catalyst for the latter, free-radical chlorination; the reaction is best effected in the presence of a light source; the catalyst can be reused many times with no loss in activity.Both reaction modes, the ionic (ring chlorination)and the radical (side-chain substitution), are likely to occur outside of the channel network in the microporous solid.The effects of various experimental factors - such as the nature of the solvent, the reaction time and temperature, the Broensted acidity of the solid support, the presence of radical inhibitors, and the quantity of catalysts - were investigated.The procedures resulting from this study are very easy to implement in practice and are quite effective.
Delaude, Lionel,Laszlo, Pierre
p. 5260 - 5269
(2007/10/02)

AN EFFECTIVE CHLORINATING AGENT BENZYLTRIMETHYLAMMONIUM TETRACHLOROIODATE, BENZYLIC CHLORINATION OF ALKYLAROMATIC COMPOUNDS
The reaction of alkylaromatic compounds with benzyltrimethylammonium tetrachloroiodate in carbon tetrachloride in the presence of AIBN under reflux for several hours gave α-chloro-substituted compounds in fairly good yields.
Kajigaeshi, Shoji,Kakinami, Takaaki,Moriwaki, Masayuki,Tanaka, Toshio,Fujisaki, Shizuo
p. 5783 - 5786
(2007/10/02)

AN IMPROVED METHOD FOR THE CONVERSION OF CERTAIN AROMATIC CARBOXYLIC ACIDS INTO BENZYLIC CHLORIDES
A novel one-pot procedure, which affords benzylic chlorides in about 70percent yield, involves reduction of benzoyl chlorides by aqueous sodium borohydride as a key step.
Costello, Alan T.,Milner, David J.
p. 1173 - 1176
(2007/10/02)

Kinetics and Equilibria of Chloride Transfer Reactions. Stabilities of Carbocations Based on Chloride and Hydride Transfer Equilibria Measurements
The kinetics of a number of gas-phase chloride transfer reactions R0(1+)+RCl=R0Cl+R(1+) were measured with a pulsed electron high pressure mass spectrometer.Most of the reactions were found to occur near the collision limit, i.e., with rate constants k ca. 10-9 molecules-1 cm3 s-1.However, several reactions were much slower and were exhibiting negative temperature dependence, i.e., decreasing rate with increasing temperature.Hydride and chloride transfer equilibria were determined for various carbocations R(1+) (R=isopropyl, cyclopentyl, tert-butyl, 1-methylcyclopentyl, substituted benzyls, norbornyl, 2-methyl-2-norbornyl, and adamantyl).Excellent agreement with earlier hydride transfer measurements of Solomon, Meot-Ner, and Field were observed.The chloride affinities generally support conclusions based on the hydride transfer data.Discussion of the data in connection with benzyl cation substituent effects, the norbornyl cation stability, and solvent effects on carbocation stability is presented.The data show that the 2-norbornyl cation is unusually stable.Significant differences between carbocation R(1+) stabilities in gas phase and solution are found which suggest that both differential nucleophilic solvent stabilization and differential nonspecific solvation occur in solution.
Sharma, R. B.,Sharma, D. K. Sen,Hiraoka, K.,Kebarle, P.
p. 3747 - 3757
(2007/10/02)

Chlorination of Toluene and Substituted Toluenes by Trichloroisocyanuric Acid: A Kinetic Investigation
The kinetics of chlorination of toluene, o-, m- and p-xylenes, m- and p-chlorotoluenes and m-nitrotoluene by trichloroisocyanuric acid (TCCA) in aqueous acetic acid in the presence of perchloric acid (HClO4) have been studied.The reaction is first order each in and .The reaction is insensitive towards change in .Increase in the percentage of acetic acid in the reaction medium retards the reaction rate.Various thermodynamic parameters have been evaluated.A suitable mechanism is postulated taking the observed kinetic data into consideration.
Pati, Subas C.,Sarangi, Chintamani
p. 745 - 747
(2007/10/02)

ARYLMETHYL ISOCYANATES
Chloromethyl isocyanate reacts readily with aromatic hydrocarbons in the presence of anhydrous ferric chloride or other catalysts of the Friedel-Crafts reaction with the formation of arylmethyl isocyanates.The latter add alcohols and amines readily, being converted into the corresponding substituted urethanes and ureas.When heated in the presence of catalytic amounts of 1,3-dimethylphosphol-3-ene they give substituted carbodiimides.
Kozhushko, B. N.,Lomakina, A. V.,Paliichuk, Yu. A.,Shokol, V. A.
p. 654 - 660
(2007/10/02)

CONCERNING THE CHLOROMETHYLATION OF ALKYLBENZENES AND POLYSTYRENES BY CHLOROMETHYL METHYL ETHER
Chloromethyl methyl ether-stannic chloride treatments of toluene, ethylbenzene, isopropylbenzene and tert-butyl benzene afforded respectively, 26.5, 16.8, 5.5 and 2.5percent orthoproducts.No meta-products could be detected (less than 0.5percent).Similar chloroalkylation of linear polystyrenes followed by conversion of the chloromethyl groups to hydroxylmethyl, yielded products possessing 5.0 +/- .3percent ortho-substitution.
Pinnell, R. P.,Khune, G. D.,Khatri, N. A.,Manatt, S. L.
p. 3511 - 3514
(2007/10/02)

AROMATIZATION OF 1-(TRIHALOGENOMETHYL)-1-CYCLOHEXANOLS BY THE ACTION OF PHOSPHORUS(V) OXIDE - A NEW METHOD FOR THE PRODUCTION OF BENZYL HALIDES
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Shakhnazaryan, G. M.
p. 1923
(2007/10/02)

Regioselective Ring Opening in Substituted Benzocyclopropenes. An Alternative or Complementary Mechanism for Electrophilic Substitution Involving Attack at a ? Bond
2-Methylbenzocyclopropene (5) reacts with bromine, iodine, and HCl to give the m-xylenes 12a,c,d as the major products, whereas it reacts with silver nitrate in the presence of ethanol and aniline to give the o-xylenes 11e,f as the major products.Similarly, 3-methylbenzocyclopropene (10) gives mainly m-xylenes 14a,c,d with halogens and HCl and gives p-xylenes 13e,f with silver nitrate and ethanol or aniline.Cyclopropabenzocyclobutene (15) also gives different products with halogens and silver nitrate, but in this case HCl gives the same type of product as the silver ion.The difference in electrophilic behavior of 5, 10, and 15 toward the two types of reagents is suggested to arise from attack of the silver ion (and the proton in the case of 15) on the ? electrons of the cyclopropyl ring.
Bee, Lim Keow,Garratt, Peter J.,Mansuri, Muzamil M.
p. 7076 - 7079
(2007/10/02)

Process for tris(aralkyl)phosphines
In a solution that is free of bases and free of oxygen and which contains at least four molar proportions of the reactant tris(hydroxymethyl)phosphine for every three molar proportions of an aralkyl halide reactant, the following reaction produces tris(aralkyl)phosphine product: after separation of the phosphine product, the phosphonium salt by-products can be converted to tris(hydroxymethyl)phosphine by the addition of a base.
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(2008/06/13)