- New method for promoting photosensitive oxidation to remove 1, 2-mercaptoethanol acetal protecting group by utilizing visible light irradiation
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The invention discloses a new method for removing a 1, 2-mercaptoethanol acetal protecting group, and belongs to the field of organic synthetic chemistry. The method comprises the following steps of:under a room-temperature open system, adding a substrate 2-substituted-1, 3-oxo-thio-cyclopentane and a catalytic amount of a photosensitizer Eosin Y into a proper amount of acetonitrile; and performing irradiating with a blue LED lamp for 3 hours while stirring to obtain the corresponding aldehyde compound with favorable yield. The method has the advantages of mild operation conditions, greenness, environmental protection, no harsh water and oxygen removal operation and device, realization of the reaction at room temperature, high substrate conversion rate, simple and easy post-treatment, andprovides a good method for removing the 1, 2-mercaptoethanol acetal protecting group at present.
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Paragraph 0014-0016
(2021/01/30)
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- Visible light photoredox catalyzed deprotection of 1,3-oxathiolanes
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An efficient visible light photoredox catalyzed aerobic deprotection of 1,3-oxathiolanes using organic dye Eosin Y as a photocatalyst is disclosed. The deprotection procedure features the use of a metal-free catalyst, mild conditions, a broad range of substrate scope, and good functional group tolerance. 35 examples were tested under the standard conditions and most of them afforded the deprotected products in modest to high yields.
- Yang, Mingyang,Xing, Zhimin,Fang, Bowen,Xie, Xingang,She, Xuegong
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supporting information
p. 288 - 291
(2020/01/13)
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- Synthesis method of O-formyl benzoic acid
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The invention discloses a synthesis method of o-formyl benzoic acid. The synthesis method includes the following steps that (1) 20 mL of o-dimethyl benzene is taken and placed in a reactor, the reactor is heated to 130 to 135 DEG C, and DMF, a catalyst and a cocatalyst are added in turn; (2) reaction liquid is cooled to the room temperature, and an obtained clear colorless crystal is o-methyl benzonitrile; and (3) the o-methyl benzonitrile is placed in the reactor, and heated to 110 to 115 DEG C, the DMF, the catalyst and the cocatalyst are added, oxygen intake is controlled to be 900 mL/min,hydrogen intake is controlled to be 100 mL/min, reaction is conducted for 2 to 3 h, and the o-formyl benzoic acid can be obtained through hydrolysis of obtained white crystalline powder under the acidic condition. The o-methyl benzonitrile is synthesized by a one-step method of liquid phase ammoxidation of o-xylene under normal pressure, then the o-formyl benzoic acid is synthesized by further oxidation of the o-methyl benzonitrile, the yield is high, the purity of product is high, and the requirements on equipment are low.
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Paragraph 0009 0011-0012
(2019/12/25)
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- Synthesis of Renewable meta-Xylylenediamine from Biomass-Derived Furfural
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We report the synthesis of biomass-derived functionalized aromatic chemicals from furfural, a building block nowadays available in large scale from low-cost biomass. The scientific strategy relies on a Diels–Alder/aromatization sequence. By controlling the rate of each step, it was possible to produce exclusively the meta aromatic isomer. In particular, through this route, we describe the synthesis of renewably sourced meta-xylylenediamine (MXD). Transposition of this work to other furfural-derived chemicals is also discussed and reveals that functionalized biomass-derived aromatics (benzaldehyde, benzylamine, etc.) can be potentially produced, according to this route.
- Scodeller, Ivan,Mansouri, Samir,Morvan, Didier,Muller, Eric,de Oliveira Vigier, Karine,Wischert, Raphael,Jér?me, Fran?ois
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supporting information
p. 10510 - 10514
(2018/08/17)
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- Preparation method of aromatic nitrile compound or heteroaromatic nitrile compound
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The invention discloses a preparation method of an aromatic nitrile compound or a heteroaromatic nitrile compound. The preparation method comprises: under the protection of an inert gas, in a solvent,under the actions of a nickel catalyst, a ligand, metal zinc and an additive, carrying out a reaction on a cyanation reagent and halogenated aromatic hydrocarbon or halogenated heteroaromatic hydrocarbon. According to the present invention, by using the inexpensive and easily-available nickel catalyst and the ligand, the halogenated aromatic hydrocarbon or halogenated heteroaromatic hydrocarbon,especially the chlorinated aromatic hydrocarbon or chlorinated heteroaromatic hydrocarbon with characteristics of low price, easy obtaining and low reaction activity can mildly and efficiently react with the cyanation reagent with low toxicity to prepare the aromatic nitrile compound or heteroaromatic nitrile compound; and the preparation method has advantages of simple operation, mildness, high efficiency and the like, and further has characteristics of good functional group compatibility, good universality of substrate and the like.
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Paragraph 0043; 0045; 0145-0147
(2018/11/03)
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- Visible-Light-Promoted Nickel- and Organic-Dye-Cocatalyzed Formylation Reaction of Aryl Halides and Triflates and Vinyl Bromides with Diethoxyacetic Acid as a Formyl Equivalent
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A simple formylation reaction of aryl halides, aryl triflates, and vinyl bromides under synergistic nickel- and organic-dye-mediated photoredox catalysis is reported. Distinct from widely used palladium-catalyzed formylation processes, this reaction proceeds by a two-step mechanistic sequence involving initial in situ generation of the diethoxymethyl radical from diethoxyacetic acid by a 4CzIPN-mediated photoredox reaction. The formyl-radical equivalent then undergoes nickel-catalyzed substitution reactions with aryl halides and triflates and vinyl bromides to form the corresponding aldehyde products. Significantly, besides aryl bromides, less reactive aryl chlorides and triflates and vinyl halides serve as effective substrates for this process. Since the mild conditions involved in this reaction tolerate a plethora of functional groups, the process can be applied to the efficient preparation of diverse aromatic aldehydes.
- Huang, He,Li, Xiangmin,Yu, Chenguang,Zhang, Yueteng,Mariano, Patrick S.,Wang, Wei
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supporting information
p. 1500 - 1505
(2017/02/05)
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- PRODUCTION OF XYLENE DERIVATIVES
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The present invention relates to the production of xylene derivatives from furfural and its derivatives. The invention describes new routes for converting furfural and its derivatives into xylene derivatives including novel intermediates.
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Page/Page column 21; 22; 23; 24
(2017/07/06)
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- General and Mild Nickel-Catalyzed Cyanation of Aryl/Heteroaryl Chlorides with Zn(CN)2: Key Roles of DMAP
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A new and general nickel-catalyzed cyanation of hetero(aryl) chlorides using less toxic Zn(CN)2 as the cyanide source has been developed. The reaction relies on the use of inexpensive NiCl2·6H2O/dppf/Zn as the catalytic system and DMAP as the additive, allowing the cyanation to occur under mild reaction conditions (50-80 °C) with wide functional group tolerance. DMAP was found to be crucial for successful transformation, and the reaction likely proceeds via a Ni(0)/Ni(II) catalysis based on mechanistic studies. The method was also successfully extended to aryl bromides and aryl iodides.
- Zhang, Xingjie,Xia, Aiyou,Chen, Haoyi,Liu, Yuanhong
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supporting information
p. 2118 - 2121
(2017/04/27)
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- N-Functionalized Amino Acids Promoted Aerobic Copper-Catalyzed Oxidation of Benzylic Alcohols in Water
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Instead of traditional N,N-bidentate ligands, N-functionlized amino acids were used as powerful N,O-bidentate ligands in aerobic copper/TEMPO-catalyzed system for promoting oxidation of benzylic alcohols. Under the optimized reaction conditions, a wide range of primary and secondary benzylic alcohols have been efficiently converted into aldehydes and ketones with good to excellent yields in water.
- Zhang, Guofu,Lei, Jie,Han, Xingwang,Luan, Yuxin,Ding, Chengrong,Shan, Shang
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p. 779 - 784
(2015/03/30)
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- Mild and rapid hydroxylation of aryl/heteroaryl boronic acids and boronate esters with N-oxides
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Aryl and heteroaryl boronic acids and boronate esters are rapidly, often within minutes, transformed into the corresponding phenols by N-oxides in an open flask at ambient temperature. This transformation has broad compatibility with a variety of functional groups.
- Zhu, Chen,Wang, Rui,Falck
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supporting information; experimental part
p. 3494 - 3497
(2012/08/28)
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- Oxidation of benzylic azides catalysed by iron(III) chloride with hydrogen peroxide as oxidant
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A simple and general method for the oxidation of benzylic azides to aldehydes using the inexpensive and environmentally benign iron (III) chloride as catalyst with 30% aqueous H2O2 as oxidant is described. Broad substrate scope and high tolerance against several functional groups make the process synthetically useful.
- Zhang, Hong-Ping,Dai, You-Zhi,Tao, Li-Ming
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experimental part
p. 720 - 722
(2012/03/09)
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- ACID-SENSITIVE LINKERS FOR DRUG DELIVERY
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The invention is in general directed to acid-sensitive linkers, and methods of use thereof, such as, for example, in drug delivery methods.
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Page/Page column 9-11
(2011/04/14)
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- Sulfate additives generate robust and highly active palladium catalysts for the cyanation of aryl chlorides
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The use of sulfate additives such as H2SO4 greatly increases the reactivity of palladium catalysts for the cyanation of aryl and heteroaryl chlorides and renders them more robust toward adventitious air. Using this method, a wide variety of aromatic and heteroaromatic nitriles were prepared in high yield.
- Shevlin, Michael
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experimental part
p. 4833 - 4836
(2010/10/02)
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- Correlation analysis of reactivity in the oxidation of substituted benzyl alcohols by morpholinium chlorochromate
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Oxidation of benzyl alcohol and some ortho-, meta- andparo-monosubstitutcd derivatives by morpholinium chlorochromate in dimethyl stilphoxide leads to the formation of corresponding benzaldehydcs. The reaction is first order each in both morpholinium chlorochromate and the alcohol. The reaction is promoted by hydrogen ions; the hydrogen-ion dependence has the form kob8 = a + b [H+]. Oxidation of α,α-dideuteriobenzyl alcohol exhibits a substantial primary kinetic isotope effect (kH/kD = 5.86 at 298 K). The reaction has been studied in nineteen organic solvents and the effect of solvent analysed using Taft's and Swain's multi-parametric equations. The rates of oxidation of para- and meta-substituted benzyl alcohols have been correlated in terms of Charton's tripararnetric LDR equation whereas the oxidation of ortho-substituted benzyl alcohols with tetraperametric LDRS equation. The oxidation of para-substituted benzyl alcohols is more susceptible to the derealization effect than that of ortho- and meta- substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the ortho-substituents. A suitable mechanism is also proposed.
- Soni, Neelam,Tiwari, Vandana,Sharma, Vinita
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scheme or table
p. 669 - 676
(2009/02/08)
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- Correlation analysis of reactivity in the oxidation of substituted benzyl alcohols by 2,2′-bipyridinium chlorochromate
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Oxidation of benzyl alcohol and some ortho-, meta- and para-monosubstituted ones by 2.2′-bipyridinium chlorochromate (BPCC) in DMSO leads to the formation of corresponding benzaldehydes. The reaction is first order in both BPCC and the alcohol. The reaction is promoted by hydrogen ions; the hydrogen-ion dependence has the form : kobs = a + b [H+]. Oxidation of α,α-dideuteriobenzyl alcohol (PhCD2OH) has exhibited a substantial primary kinetic isotope effect (kH/k D = 5.60 at 298 K). The reaction has been studied in nineteen organic solvents and the effect of solvent analysed using Taft's and Swain's multi-parametric equations. The rates of oxidation of para- and meta-substituted benzyl alcohols have been correlated in terms of Charton's triparametric LDR equation whereas the oxidation of ortho-substituted benzyl alcohols with tetraparametric LDRS equation. The oxidation of para-substituted benzyl alcohols is more susceptible to the delocalization effect than that of ortho- and meta-substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the ortho-substituents. A suitable mechanism has been proposed.
- Yajurvedi, Deeksha,Baghmar, Manju,Sharma, Pradeep K.
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body text
p. 496 - 501
(2009/07/18)
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- A tandem elimination-cyclization-suzuki approach: Efficient one-pot synthesis of functionalized (Z)-3-(arylmethylene)isoindolin-1-ones
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(Chemical Equation Presented) A novel and efficient one-pot regioselective elimination-cyclization-Suzuki approach was developed to afford (Z)-3-arylmethyleneisoindolin-1-ones in good to excellent yields from easily accessible o-gem-dihalovinylbenzamides and organoboron reagents.
- Sun, Caiyun,Xu, Bin
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supporting information; experimental part
p. 7361 - 7364
(2009/05/07)
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- Palladium-catalyzed reductive carbonylation of aryl triflates with synthesis gas
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A general palladium-catalyzed reductive carbonylation of aryl triflates in the presence of synthesis gas (CO/H2) has been developed. The reaction with this most simple and environmentally benign formylation source proceeds under mild conditions and various aromatic aldehydes have been prepared in good to high yield. Georg Thieme Verlag Stuttgart.
- Brennfuhrer, Anne,Neumann, Helfried,Beller, Matthias
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p. 2537 - 2540
(2008/02/13)
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- Reductive carbonylation - An efficient and practical catalytic route for the conversion of aryl halides to aldehydes
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Alternative routes for the introduction of aldehyde functionality are particularly desirable for fine chemical and pharmaceutical intermediates because of the wide range of further transformations that are possible. Catalytic processes are of particular interest for minimising waste, and therefore the reductive carbonylation of aryl halides has been explored. We have shown that high yields of aldehydes may be obtained for a wide selection of aryl iodides and bromides using mild conditions (3 bar of CO, temperatures 60-120°C) and silanes as hydride source. A choice of conditions (catalyst, base, solvent) is required to cover the range of aryl substituents varying in electron donation and steric influence. This is related to the competing needs of the several steps of this reaction, including oxidative addition, CO substitution, CO insertion, hydride transfer, and reductive elimination.
- Ashfield, Laura,Barnard, Christopher F. J.
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- Correlation analysis of reactivity in the oxidation of substituted benzyl alcohols by quinolinium bromochromate
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Oxidation of benzyl alcohol and some ortho- meta- and para-monosubstituted ones by quinolinium, bromochromate (QBC) in dimethyl sulphoxide (DMSO) leads to the formation of corresponding benzaldehydes. The reaction is first order each in both QBC and the alcohol. The reaction is promoted by hydrogen ions; the hydrogen-ion dependence has the form kobs = a + b [H+]. Oxidation of α,α-dideuteriobenzyl alcohol (PhCD2OH) has exhibited a substantial primary kinetic isotope effect (kH/k D = 5.60 at 298 K). The reaction has been studied in nineteen organic solvents and the effect of solvent analysed using Taft's and Swain's multi-parametric equations. The rates of oxidation of para- and meta-substituted benzyl alcohols have been correlated in terms of Charton's triparametric LDR equation whereas the oxidation of ortho-substituted benzyl alcohols with tetraparametric LDRS equation. The oxidation of para-substituted benzyl alcohols is more susceptible to the delocalization effect than that of ortho- and meta-substituted compounds which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the ortho-substituents. A suitable mechanism has been proposed.
- Prakash, Om,Sharma, Pradeep K.
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p. 467 - 473
(2007/10/03)
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- Kinetics and mechanism of the oxidation of substituted benzyl alcohols by [bis(trifluoroacetoxy)iodo]benzene
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The oxidation of substituted benzyl alcohols by bis(trifluoroacetoxy)iodo] benzene in aqueous acetic acid solution results in the formation of the corresponding benzaldehydes. The reaction is first order with respect to each of the alcohol, TFAIB and hydrogen ions. The oxidation of [1,1-2H 2]benzyl alcohol exhibited the presence of a substantial primary kinetic isotope effect, indicating the cleavage of the α-C-H bond in the rate-determining step. Increase in the amount of water, in the solvent mixture of acetic acid and water, results in a decrease of the reaction rate. The analysis of the substituent effect in terms of Charton's LDR equation yielded an excellent correlation with negative reaction constants. A mechanism involving a hydride-ion transfer in the rate-determining step has been proposed.
- Kansara, Alpna,Sharma, Pradeep K.,Banerji, Kalyan K.
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p. 581 - 584
(2007/10/03)
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- 4-HYDROXPIPERIDINE DERIVATIVE WITH ANALGETIC ACTIVITY
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A compound represented by the following Formula (I): (wherein A represents oxygen atom or -NR3- (R3 represents hydrogen atom or lower alkyl group); R1 represents nitro group, lower alkoxycarbonyl group, carbamoyl group unsubstituted or mono- or di-substituted by lower alkyl group, unprotected or protected hydroxyl group, unprotected or protected carboxyl group, lower alkyl group substituted by unprotected or protected hydroxyl group, or tetrazolyl group; and R2 represents hydrogen atom, cyano group or lower alkylsulfonyl group, provided that when A is - NR3-, it is excluded that R1 represents unprotected or protected hydroxyl group or lower alkyl group substituted by unprotected or protected hydroxyl group) or its salt, and method for producing the compound, and a pharmaceutical composition containing the compound as active ingredient.
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- Correlation analysis of reactivity in the oxidation of substituted benzyl alcohols by quinolinium fluorochromate
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Oxidation of benzyl alcohol and some ortho-, meta- and para-monosubstituted ones by quinolinium fluorochromate (QFC) in dimethyl sulphoxide (DMSO) leads to the formation of corresponding banzaldehydes. The reaction is first order each in both QFC and the alcohol. The reaction is promoted by hydrogen ions; the hydrogen-ion dependence has the form kobs= a + b [H+]. Oxidation of α,α-dideuteriobenzyl alcohol (PhCD2OH) has exhibited a substantial primary kinetic isotope effect. The reaction has been studied in nineteen organic solvents and the effect of solvent analysed using Taft's and Swain's multi-parametric equations. The rates of oxidation of para- and meta-substituted benzyl alcohols have been correlated in terms of Charton's triparametric LDR equation, whereas the oxidation of ortho-substituted benzyl alcohols with tetraparametric LDRS equation. The oxidation of para-substituted benzyl alcohols is more susceptible to the delocalization effect than that of ortho- and meta-substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the ortho-substituents. A suitable mechanism has been proposed.
- Dave, Itishri,Sharma, Vinita,Banerji, Kalyan K.
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p. 493 - 499
(2007/10/03)
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- Correlation analysis of reactivity in oxidation of substituted benzyl alcohols by tetrabutylammonium tribromide
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Oxidation of benzyl alcohol and some ortho-, meta- and para-monosubstituted benzyl alcohols by tetrabutylammonium tribromide (TBATB) in aqueous acetic acid leads to the formation of corresponding benzaldehydes. The reaction is first order each in TBATB and the alcohol. The oxidation of [1,1-2H2]benzyl alcohol (PhCD2OH) exhibited a substantial kinetic isotope effect. Addition of tetrabutylammonium chloride or potassium bromide did not affect the rate. Tribromide ion has been postulated as the reactive oxidizing species. The reaction rate increases with increase in the polarity of the solvent. The rates of oxidation of meta- and para-substituted benzyl alcohols showed excellent correlation in terms of Charton's triparametric LDR, equation whereas the oxidation of ortho-substituted benzyl alcohols correlated best with the LDRS equation. The oxidation of para-substituted benzyl alcohols is more susceptible to the delocalization effect than is the oxidation of ortho- and meta-substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subject to steric acceleration by the ortho-substituents. A suitable mechanism is proposed. Copyright
- Kumar, Ashok,Sharma, Pradeep K.,Banerji, Kalyan K.
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p. 721 - 727
(2007/10/03)
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- Correlation analysis of reactivity in oxidation of substituted benzyl alcohols by benzyltrimethylammonium chlorobromate
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Oxidation of benzyl alcohol and some ortho-, meta- and para-monosubstituted benzyl alcohols by benzyltrimethylammonium chlorobromate (BTMACB) in aqueous acetic acid leads to the formation of corresponding benzaldehydes. The reaction is first order each in BTMACB and the alcohol. The oxidation of α,α-dideuteriated benzyl alcohol (PhCD2OH) exhibits a substantial kinetic isotope effect. Addition of benzyltrimethylammonium chloride or potassium bromide ions does not affect the rate. Chlorobromate ion has been postulated as the reactive oxidizing species. The effect of solvent composition indicates that the reaction rate increases with an increase in the polarity of the solvent. The rates of oxidation of meta- and para-substituted benzyl alcohols have been correlated in terms of Charton's triparametric LDR equation whereas the oxidation of ortho-substituted benzyl alcohols has been correlated with tetraparametric LDRS equation. The oxidation of para-substituted benzyl alcohols is more susceptible to the delocalization effect than is the oxidation of ortho- and meta-substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the ortho-substituents. A suitable mechanism has been proposed.
- Sita Rama Raju,Sharma,Banerji
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p. 1258 - 1263
(2007/10/03)
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- Isoquinoline compound melanocortin receptor ligands and methods of using same
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The invention relates to melanocortin receptor ligands and methods of using the ligands to alter or regulate the activity of a melanocortin receptor. The invention further relates to tetrahydroisoquinoline aromatic amines that function as melanocortin receptor ligands and as agents for controlling cytokine-regulated physiologic processes and pathologies, and combinatorial libraries thereof.
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- Investigation on the photoreactions of nitrate and nitrite ions with selected azaarenes in water
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The photoreactions of selected azaarenes with nitrate and nitrite ions were investigated under irradiation at λ = 313 nm. The excitation of both anions leads to several photochemical reactions forming mainly hydroxyl radicals and nitrogen oxides. The purification capability of natural waters i.e. the oxidation of inorganic and organic substances results from the formation of hydroxyl radicals. Nitrated isomers of azaarenes were found among the main products of the investigated photoreactions. The nitrogen oxides were responsible for the production of nitrated derivatives which possess a high toxic potential. Their formation was explained by the parallel occurance of two mechanism, a molecular and a radical one. The molecular mechanism became more important with increasing ionisation potentials of the azaarenes. The spectrum of oxidized products corresponded to the one got in the photoreactions of azaarenes with hydrogen peroxide. The formation of several oxidation and nitration products of the pyridine ring with its low electron density was explained by the reaction of excited states of azaarenes. The photoreactions with nitrite ions only led to the formation of oxidized and nitrated products. Nitroso products were not formed. The reactivity of nitrogen monoxide is too low for its reaction with the azaarenes.
- Beitz, Toralf,Bechmann, Wolfgang,Mitzner, Rolf
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p. 351 - 361
(2007/10/03)
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- Process for the preparation of benzaldehydes
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Benzaldehydes of the formula STR1 can be obtained by reaction of substituted β-amino-styrenes of the formula STR2 in which R1, R2, R3, R4, R5, R8, R9, R10, m, n and o have the scope of meaning indicated in the description, with oxygen in the presence of a Cu compound in the solution of an aprotic polar solvent at 0°-120° C.
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- Unusual Regioselectivity in the Carbonylation of Substituted Benzenes via the C-H Activation Catalyzed by RhCl(CO)(PMe3)2
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Meta-substituted benzaldehydes were obtained as the major product in the carbonylation of mono-substituted benzenes via the C-H activation catalyzed by RhCl(CO)(PMe3)2 under irradiation.
- Sakakura, Toshiyasu,Tanaka, Masato
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p. 1113 - 1116
(2007/10/02)
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- Cyanation of Aromatic Compounds in a Gaseous Plasma
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Aromatic compounds are directly cyanated by passing cyanogen and the respective compounds through a radio-frequency generated and inductively coupled glow discharge zone.Benzene and a wide variety of substituted benzenes (C6H5X: X = CH3, t-Bu, CF3, OH, F, Cl, Br, CHO) are cyanated providing a good yield of ortho-, meta-, para-, and ipso-substituted products.The relative amount of ipso product increases as the carbon-X bond dissociation energy decreases.The ratio of ortho to meta to para cyanated products demonstrates a slight preference for substitution on electron-rich positions.A plot of the meta/para yield ratio against ?m - ?p gives a ρ value of -0.5.It is proposed that electron impact on cyanogen produces CN., which in turn attacks the aromatic, causing substitution.
- So, Y. H.,Miller, Larry L.
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p. 4204 - 4209
(2007/10/02)
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- PHOTOOXYGENATION OF 7-SUBSTITUTED CYCLOHEPTATRIENES
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Photooxygenation of 7-substituted cycloheptatrienes, including the Me, Et, iPr, Ph, CN, COOMe, COOEt, and CONH2 groups was studied, and several products among the tropilidene-type (1 and 2) and norcaradiene-type (3 and 4) endoperoxides, o-substituted benzaldehydes (5), diepoxides (6 and 7), and ketoalcohols (8) were obtained.Mechanism of the formations of the products was discussed.Thermal isomerization of the endoperoxides (1, 3 and 4) to the corresponding diepoxides (10, 6 and 7), and the reaction of the endoperoxides (1 and 3) with triethylamine were examined.
- Asao, Toyonobu,Yagihara, Morio,Kitahara, Yoshio
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p. 985 - 991
(2007/10/02)
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