- Conversion of Aryl Aldehydes to Benzyl Iodides and Diarylmethanes by H3PO3/I2
-
For the first time, H3PO3 was used as both the reducing reagent and the promotor in the reductive benzylation reactions with aryl aldehydes. By using a H3PO3/I2 combination, various aromatic aldehydes underwent iodination reactions and Friedel-Crafts type reactions with arenes via benzyl iodide intermediates, readily producing benzyl iodides and diarylmethanes in good yields. Intramolecular cyclization reactions also took place, giving the corresponding cyclic compounds. This new strategy features easy-handling, low-cost, and metal-free conditions.
- Lv, Fang,Xiao, Jing,Xiang, Junchun,Guo, Fengzhe,Tang, Zi-Long,Han, Li-Biao
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p. 3081 - 3088
(2021/02/01)
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- Preparation method of benzyl iodide and derivatives thereof
-
The invention discloses a preparation method of benzyl iodide and derivatives thereof, which comprises the following steps: in a protective atmosphere, carrying out heating reaction on aryl aldehyde and iodine elementary substance in the presence of a solvent and phosphorous acid to obtain benzyl iodide and derivatives thereof. According to the method, cheap and green solid phosphorous acid is selected as a reduction reagent for reaction, elemental iodine is selected as an iodine source, the benzyl iodide and the derivatives thereof are efficiently prepared from the aryl aldehyde compounds which are simple and easy to obtain by a one-pot one-step method under mild conditions, and the method has the advantages of simplicity in operation, cheap and easily available reagents, environmental friendliness and the like; and the use of expensive silicon-hydrogen compounds and transition metal catalysts is avoided, and the yield can reach 94% at most, so that the method is beneficial to industrial production.
- -
-
Paragraph 0049-0052
(2021/05/01)
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- Iminophosphorane-mediated regioselective umpolung alkylation reaction of α-iminoesters
-
Umpolung reactions of imines, especially the asymmetric reactions, have been extensively studied as they provide access to important chiral amines in an efficient manner. The reactions studied range from simple Michael reactions to several kinds of other reactions such as the aza-benzoin reaction, aza-Stetter reaction, addition with MBH carbonate, and Ir-catalysed allylation. Herein, we report the first umpolung alkylation reaction of α-iminoesters with alkyl halides mediated by iminophosphorane as an organic superbase. The desired products were obtained in up to 82% yield with almost perfect regioselectivities. The key to the regioselectivity of this reaction was the use of 4-trifluoromethyl benzyl imines as a substrate. The products were successfully derivatised into the more functionalised molecules in good yields.
- Kukita, Mayu,Mino, Takashi,Omori, Kazuki,Sakamoto, Masami,Yoshida, Yasushi
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p. 4551 - 4564
(2021/05/31)
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- Method for efficiently preparing benzyl iodide and derivatives thereof
-
The invention discloses a method for efficiently preparing benzyl iodide and derivatives thereof. The benzyl iodide and the derivatives thereof are prepared by using a benzaldehyde compound as the initial raw material through complex reaction, main reaction and post-reaction. The method specifically includes: placing rhodium and phosphine ligand into a reaction container, adding an organic solvent, stirring for complexing to obtain a reaction system a, adding iodine, stirring under room temperature, adding the initial material benzaldehyde compound to continuously perform stirring reaction toobtain reaction liquid b, transferring into a high-pressure reaction kettle, performing gas replacement, filling hydrogen, keeping positive pressure, performing reaction under room temperature for 4-48 hours to obtain reaction liquid c, and performing vacuum concentration and column chromatography purification to obtain the target benzyl iodide and the derivatives thereof. The method is cheap in used substrate, simple to operate, good in reaction operation safety, environmentally friendly, high in yield, high in the purity of the benzyl iodide and the derivatives thereof, easy to achieve large-scale production and capable of achieving industrial production to satisfy social medical requirements.
- -
-
Paragraph 0026-0028
(2020/07/12)
-
- Preparation method of benzyl iodide and derivatives thereof
-
The invention discloses a preparation method of benzyl iodide and derivatives thereof. The preparation method comprises the following steps: under the reduction action of sodium borohydride, a benzylalcohol compound shown as a formula I reacts with elemental iodine to obtain benzyl iodide shown as a formula II and derivatives thereof; in the formula I and the formula II, R represents one or moresubstituents on a benzene ring and is selected from at least one of aryl, substituted or unsubstituted alkyl, halogen and nitro. The preparation method of benzyl iodide and derivatives thereof is scientific and reasonable, sodium borohydride which is mild in reactivity, low in price and easily available is used as a reducing agent, and elemental iodine is convenient and easily available; in addition, the preparation method has the characteristics of simplicity and convenience in operation, high synthesis yield, easiness in product purification, environmental friendliness and the like.
- -
-
Paragraph 0077-0081
(2020/06/09)
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- Cuprous complex containing diphospho-ortho-carborane ligand as well as preparation method and application thereof (by machine translation)
-
The method comprises the following steps, adding :1) solution to the ortho-carborane solution n - BuLi, reacting, at room temperature for 30 - 60min;2), adding, and reacting 1 - 3h;3) with high yield CuI, of the monovalent copper complex to react alcohol and iodide to synthesize the iodo-hydrocarbon 3 - 6h, and synthesizing the iodo-hydrocarbon; through post-treatment at room temperature for synthesizing the iodo-copper complex, by the following steps: reacting the alcohol with the iodide at room temperature and carrying out post-treatment to obtain the monovalent copper complex . The preparation method comprises the following steps: catalyzing alcohol and iodide to react with the iodide, to synthesize the iodo- hydrocarbyl complex; and the method comprises the following steps: catalyzing alcohol and iodide to react. (by machine translation)
- -
-
Paragraph 0047-0049; 0052-0056
(2020/05/02)
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- Rhodium-Catalyzed Generation of Anhydrous Hydrogen Iodide: An Effective Method for the Preparation of Iodoalkanes
-
The preparation of anhydrous hydrogen iodide directly from molecular hydrogen and iodine using a rhodium catalyst is reported for the first time. The anhydrous hydrogen iodide generated was proven to be highly active in the transformations of alkenes, phenyl aldehydes, alcohols, and cyclic ethers to the corresponding iodoalkanes. Therefore, the present methodology not only has provided convenient access to anhydrous hydrogen iodide but also offers a practical preparation method for various iodoalkanes in excellent atom economy.
- Zeng, Chaoyuan,Shen, Guoli,Yang, Fan,Chen, Jingchao,Zhang, Xuexin,Gu, Cuiping,Zhou, Yongyun,Fan, Baomin
-
supporting information
p. 6859 - 6862
(2018/10/25)
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- Aliphatic C-H Bond Iodination by a N-Iodoamide and Isolation of an Elusive N-Amidyl Radical
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Contrary to C-H chlorination and bromination, the direct iodination of alkanes represents a great challenge. We reveal a new N-iodoamide that is capable of a direct and efficient C-H bond iodination of various cyclic and acyclic alkanes providing iodoalkanes in good yields. This is the first use of N-iodoamide for C-H bond iodination. The method also works well for benzylic C-H bonds, thereby constituting the missing version of the Wohl-Ziegler iodination reaction. Mechanistic details were elucidated by DFT computations, and the N-centered radical derived from the used N-iodoamide, which is the key intermediate in this process, was matrix-isolated in a solid argon matrix and characterized by UV-vis as well as IR spectroscopy.
- Artaryan, Alexander,Mardyukov, Artur,Kulbitski, Kseniya,Avigdori, Idan,Nisnevich, Gennady A.,Schreiner, Peter R.,Gandelman, Mark
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supporting information
p. 7093 - 7100
(2017/07/26)
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- A mild and highly chemoselective iodination of alcohol using polymer supported DMAP
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The synthesis of organic compounds using polymer supported catalysts and reagents, where the required product is always in solution, has been of great interest in recent years, both in industries and academia especially in pharmaceutical research. Here, a simple and efficient method for conversion of alcohols into their iodides in high yield using polymer supported 4-(Dimethylamino)pyridine (DMAP) is described. Polymer supported DMAP is used in catalytic amount and is recovered and reused several times. Additionally, this method is highly chemoselective. [Figure not available: see fulltext.]
- Das, Diparjun,H Anal, Jasha Momo,Rokhum, Lalthazuala
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p. 1695 - 1701
(2017/03/08)
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- Novel aminotetrazole derivatives as selective STAT3 non-peptide inhibitors
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The development of inhibitors blocking STAT3 transcriptional activity is a promising therapeutic approach against cancer and inflammatory diseases. In this context, the selectivity of inhibitors against the STAT1 transcription factor is crucial as STAT3 and STAT1 play opposite roles in the apoptosis of tumor cells and polarization of the immune response. A structure-based virtual screening followed by a luciferase-containing promoter assay on STAT3 and STAT1 signaling were used to identify a selective STAT3 inhibitor. An important role of the aminotetrazole group in modulating STAT3 and STAT1 inhibitory activities has been established. Optimization of the hit compound leads to 23. This compound inhibits growth and survival of cells with STAT3 signaling pathway while displaying a minimal effect on STAT1 signaling. Moreover, it prevents lymphocyte T polarization into Th17 and Treg without affecting their differentiation into Th1 lymphocyte.
- Pallandre, Jean-René,Borg, Christophe,Rognan, Didier,Boibessot, Thibault,Luzet, Vincent,Yesylevskyy, Semen,Ramseyer, Christophe,Pudlo, Marc
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supporting information
p. 163 - 174
(2015/09/21)
-
- 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)
-
- Design, synthesis and anticancer activities of novel otobain derivatives
-
A series of novel racemic otobain derivatives was designed and synthesised using 2-piperonyl-1,3-dithianes in the conjugate addition-alkylation to 5H-furan-2-one, followed by cationic cyclisation. All the synthesised compounds were consequently evaluated for their anticancer activity against several human cancers in vitro. The efficacy of the most active compound 27g was comparable with etoposide, with IC50 values ranging from 1.06 μM to 4.16 μM in different cancer cell lines. Notably, compound 27g strongly induced cell cycle arrest and increased the expression of mitosis-specific markers MPM-2 and phosphorylated histone H3, but it did not trigger cell apoptosis. Further a colony formation assay showed that compound 27g effectively inhibited the anchor growth of lung cancer cells in a dose-dependent manner. More importantly, compound 27g at 40 mg kg-1 significantly suppressed tumour volume (P 0.01) and tumour weight (P 0.05) in a human lung cancer cell xenograft mouse model without causing systematic toxicity in mice. Our findings indicated that compound 27g has significant potential for further drug development.
- Li, Zhongzhou,Su, Hui,Yu, Weiwei,Li, Xinjun,Cheng, Hao,Liu, Mingyao,Pang, Xiufeng,Zou, Xinzhuo
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p. 277 - 287
(2015/12/30)
-
- Application of "click" chemistry in solid phase synthesis of alkyl halides
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A convenient and highly selective microwave assisted procedure for the conversion of allylic, benzylic and aliphatic alcohols to their corresponding halides using polymer-bound triphenylphosphine and iodine is presented. In case of symmetrical diols, mono-iodination product is obtained in very high yield. Additionally, highly regioselective behavior is observed in our procedure. Simplicity in operation, no column chromatography required for the purification of the products, recyclability of the reagents used, short reaction times and good to excellent yields are the advantages of our protocol. Most functional groups remain unaffected under our reaction condition.
- Das, Diparjun,Chanda, Tridib,Rokhum, Lalthazuala
-
p. 775 - 783
(2016/01/20)
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- PROCESS FOR THE PREPARATION OF N-IODOAMIDES
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The present invention provides new stable crystalline N-iodoamides - 1-iodo- 3,5,5-trimethylhydantoin (1-ITMH) and 3-iodo-4,4-dimethyl-2-oxazolidinone (IDMO). The present invention further provides a process for the preparation of organic iodides using N-iodoamides of this invention and recovery of the amide co-products from waste water.
- -
-
Paragraph 00282-00283
(2015/05/26)
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- Ionic liquid-induced conversion of methoxymethyl-protected alcohols into nitriles and iodides using [Hmim][NO3]
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This Letter reports a one-pot efficient conversion of methoxymethyl-ethers into their corresponding nitriles and iodides using the ionic liquid, 1-methyl-3H-imidazolium nitrate ([Hmim][NO3]) under microwave irradiation. A variety of products were prepared in high yields using this method.
- Noei, Jalil,Mirjafari, Arsalan
-
supporting information
p. 4424 - 4426
(2014/08/05)
-
- Unexpected conversion of alkyl azides to alkyl iodides and of aryl azides to N-tert-butyl anilines
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In the presence of tert-butyl iodide, alkyl azides are converted into the corresponding iodides at room temperature, whereas, N-t-Bu anilines are obtained from aryl azides under the same experimental conditions. A mechanism is proposed to explain this unusual reactivity.
- Maury, Julien,Feray, Laurence,Bertrand, Michele P.,Kapat, Ajoy,Renaud, Philippe
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p. 9606 - 9611,6
(2020/08/20)
-
- Highly enantioselective copper-catalyzed alkylation of β-ketoesters and subsequent cyclization to spirolactones/bi-spirolactones
-
Cu-catalyzed enantioselective alkylation of β-ketoesters using alcohols for in situ preparation of alkylating reagents is reported. A number of functionalized β-ketoesters containing a quaternary carbon stereocenter are obtained with up to 99% ee. The alkylation products derived from 2-substituted allylic alcohols or their corresponding iodides can then be converted to spirolactones, bi-spirolactones, and related chiral target products.
- Deng, Qing-Hai,Wadepohl, Hubert,Gade, Lutz H.
-
supporting information; experimental part
p. 2946 - 2949
(2012/03/26)
-
- Efficient and selective iodination of benzylic alcohols using NaI/bronsted ionic liquid system at room temperature
-
A simple, chemoselective, and effective procedure for the conversion of benzylic and allylic alcohols into corresponding iodides using NaI in the presence of a catalytic amount of 3-methylimidazolium hydrogensulfate ([Hmim]+[image omitted]) at room temperature is reported.
- Hajipour, Abdol R.,Rafiee, Fatemeh,Ruoho, Arnold
-
experimental part
p. 603 - 611
(2011/04/15)
-
- Microwave-promoted, one-pot conversion of alkoxymethylated protected alcohols into their corresponding nitriles, bromides, and iodides using [bmim][InCl4] as a green catalyst
-
The Lewis acid room temperature ionic liquid, [bmim][InCl4], was found to be an efficient and green catalyst for the highly chemoselective and one-pot conversion of MOM- or EOM-ethers into their corresponding nitriles, bromides, and iodides under microwave irradiation. The procedures are simple, rapid, and high yielding. The catalyst exhibited a remarkable reactivity and is reusable.
- Mirjafari, Arsalan,Mohammadpoor-Baltork, Iraj,Moghadam, Majid,Tangestaninejad, Shahram,Mirkhani, Valiollah,Khosropour, Ahmad Reza
-
supporting information; experimental part
p. 3274 - 3276
(2010/07/18)
-
- Establishment of heterolytic and homolytic Y-NO2 bond dissociation energy scales of nitro-containing compounds in acetonitrile: Chemical origin of NO2 release and capture
-
(Chemical Equation Presented) The first heterolytic and homolytic N(O)-NO2 bond dissociation energy scales of three types Y-nitro (Y = N, O) compounds and corresponding radical anions in acetonitrile were established by using titration calorimetry combined with relevant electrochemical data through proper thermodynamic cycles.
- Li, Xin,Zhu, Xiao-Qing,Zhang, Fan,Wang, Xiao-Xiao,Cheng, Jin-Pei
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p. 2428 - 2431
(2008/09/20)
-
- Efficient method for iodination of alcohols using KI/silica sulfuric acid (SSA)
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A straightforward and effective procedure for the conversion of benzylic and allylic alcohols to the corresponding iodides using KI/SSA in acetonitrile at room temperature. Copyright Taylor & Francis Group, LLC.
- Hajipour, Abdol R.,Zarei, Amin,Ruoho, Aronold E.
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p. 1039 - 1050
(2007/10/03)
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- Iodination of alcohols using triphenylphosphine/iodine under solvent-free conditions using microwave irradiation
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A straightforward and effective procedure for the conversion of benzylic, allylic and aliphatic alcohols to the corresponding iodides using Ph3P/I2 under solvent-free conditions using microwave irradiation is reported.
- Hajipour, Abdol Reza,Falahati, Ali Reza,Ruoho, Arnold E.
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p. 4191 - 4196
(2007/10/03)
-
- New iodination reactions of saturated hydrocarbons
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Unactivated C-H bonds react with iodine when exposed to trimethylsilyl azide in the presence of a hypervalent iodine reagent or, alternatively, to aqueous H2O2, acetic anhydride, and sodium azide (see scheme). (Chemical Equation Presented).
- Barluenga, Jose,Campos-Gomez, Esther,Rodriguez, David,Gonzalez-Bobes, Francisco,Gonzalez, Jose M.
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p. 5851 - 5854
(2007/10/03)
-
- Silica Chloride (SiO2-Cl), a New Heterogeneous Reagent, for the Selective and Efficient Conversion of Benzylic Alcohols to Their Corresponding Chlorides and Iodides
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Structurally different benzylic alcohols were efficiently converted to their corresponding chlorides by silica chloride (SiO2-Cl) in CHCl3 at room temperature. Silica chloride is also able to convert benzylic alcohols to their iodides in the presence of NaI in a mixture of CH3CN/CHCl3 in excellent yields.
- Firouzabadi, Habib,Iranpoor, Naser,Karimi, Babak,Hazarkhani, Hassan
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p. 3671 - 3677
(2007/10/03)
-
- Silica chloride in the presence of NaI is a useful system for the efficient and selective conversion of TMS, TBDMS and THP ethers into their corresponding iodides
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Direct and highly selective conversion of benzylic, allylic and propargylic TMS, TBDMS and THP ethers into their corresponding iodides with the SiO2-Cl/NaI system is described. Reactions were conducted in CH3CN at room temperature. Aliphatic silyl and tetrahydropyranyl ethers remained almost intact under similar reaction conditions.
- Firouzabadi, Habib,Iranpoor, Nasser,Hazarkhani, Hassan
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p. 7139 - 7141
(2007/10/03)
-
- A practical procedure for the synthesis of esonarimod, (R,S)-2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid, an antirheumatic agent (part 1).
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An efficient and practical procedure for the synthesis of esonarimod, (R,S)-2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid (1), a new antirheumatic drug, has been developed. The intermediate, 2-methylene-4-(4-methylphenyl)-4-oxobutanoic acid (2), was prepared by Friedel-Crafts acylation of toluene with itaconic anhydride (3) in the presence of aluminum trichloride and nitrobenzene in 63% yield without silica gel column purification. Compound 1 was prepared by Michael addition of 2 with thioacetic acid (4) in 74% yield. Overall, 1 was obtained in 47% yield from 3. The structures and synthetic mechanisms of by-products (five compounds) of 2 were also clarified.
- Noguchi, Toshiya,Onodera, Akira,Tomisawa, Kazuyuki,Yokomori, Sadakazu
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p. 1407 - 1412
(2007/10/03)
-
- A simple and efficient iodination of alcohols on polymer-supported triphenylphosphine
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A simple, mild, and high-yielding procedure for the iodination of allylic, benzylic, and other primary alcohols using a combination of iodine and imidazole on polymer-supported triphenyl phosphine is described.
- Anilkumar, Gopinathan,Nambu, Hisanori,Kita, Yasuyuki
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p. 190 - 191
(2013/09/06)
-
- Thermolysis of tert-butyl phenylperacetates: Delicate control of the rates through contributions from translational and rotational entropy
-
The first-order rate constants (ky) at several temperatures in CDCl3 were measured for thermal decompositions of YC6H4CH2CO3C(CH3) 3 with Y being p-OCH3, p-OPh, p-CH3, p-Ph, p-H, p-Cl, m-Cl, and p-NO2. The relative rates (ky/kH) exhibit excellent ρ+/σ+ Hammett correlations with ρ+ a polar TS. Activation parameters (ΔH?Y and ΔS?Y) and their differential terms (ΔΔH?Y-H and ΔΔS?Y-H) were obtained from the Eyring plot. Differential activation terms (ΔΔH?Y-H and ΔΔS?Y-H) disclose an isokinetic relation with p-CH3, p-Ph, p-H, p-Cl, and m-Cl (isokinetic temp, 230 K). However, p-OCH3, and p-OPh show negative deviations, and a positive deviation occurs with p-NO2. Plot of ΔΔH?Y-H vs σ+ exhibits a good linear relation (r = 0.95) with a slope (α1 = -3.34). A better linear correlation (r = 0.97) and steeper slope (α2 = -5.22) were observed for TΔΔS?Y-H vs σ+. Negatively larger slope (α2 = -5.22) may point to entropy control of rates. Differential activation parameters (ΔΔHS?Y-H and ΔΔS?Y-H) reflect variations of activation process. Differential activation entropies (ΔΔS?Y-H) are discussed in terms of contributions of translational and rotational entropies. Similar deviation behaviors of p-OCH3, p-OPh, and p-NO2 were again observed for the both plots. p-NO2 can strongly destabilize the cationic site of the polar TS but serves an eminent spin delocalizer for the homolytic TS.
- Kim,Baek,Tuchkin,Go
-
p. 4006 - 4011
(2007/10/03)
-
- EQUILIBRIUM PALLADIZATION OF ALKANES AND ARENES BY THE COMPLEXES OF DIHALOGENOPALLADIUM(II) AND ITS USE IN THE CATALYTIC FUNCTIONALIZATION OF HYDROCARBONS
-
The complexes of dihalogenopalladium(II) PdX2L2 (where L=PPh3, PhCN, 1/2phen) react reversibly in aromatic or saturated hydrocarbons by a mechanism of oxidative addition-reduction elimination of R-H (RH=hexane, cyclohexane, benzene, toluene, p-xylene) and form complexes of dihydrodihalogeno-organopalladium(IV), RPd(H)X2L2, capable of being converted by the action of bases into complexes of halogenoorganopalladium(II), RPdXL2.The weakest C-H bond undergoes metallation.The reaction can be used for catalytic or stoichiometric O-, S-, and P-functionalization of hydrocarbons.
- Vedernikov, A. N.,Kuramshin, A. I.,Solomonov, B. N.
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p. 1767 - 1776
(2007/10/02)
-
- Microwave irradiation promoted reactions of carboxylic acids with halides in the presence of quarternary ammonium salt
-
The reactions of carboxylic acids with halides which could not take place by conventional heating are promoted by microwave irradiation in the presence of quaternary ammonium salt as a catalyst, without a base.
- Yuan,Jiang,Gao
-
p. 3109 - 3114
(2007/10/02)
-
- REGIOSELECTIVE TRANSFORMATION OF ALLYLIC, BENZYLIC AND TERTIARY ALCOHOLS INTO THE CORRESPONDING IODIDES WITH ALUMINIUM TRIIODIDE : DEOXYGENATION OF VICINAL DIOLS
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Aluminium triiodide regioselectively converts allylic, benzylic and tertiary alcohols into the corresponding iodides in excellent yields.It also deoxygenates cis and trans secondary-tertiary and allylic bis-secondary vicinal diols in good yields.
- Sarmah, Parijat,Barua, Nabin C
-
p. 3569 - 3574
(2007/10/02)
-
- Reduction of carbonyl compounds promoted by silicon hydrides under the influence of trimethylsilyl-based reagents
-
The synthetic utility of hydrosilanes under the influence of trimethylsilyl-based reagents as new reducing systems is described. 1,1,3,3-Tetramethyldisiloxane (TMDS) reagent in combination with iodotrimethylsilane or bromotrimethylsilane produces alkyl halides from aldehydes in good to excellent yields.Polymethylhydrosiloxane (PMS) in the presence of iodotrimethylsilane also produces benzyl iodides in excellent yields.On the contrary, PMS reagent was found unsuitable for the synthesis of benzyl bromides.Similary, TMDS reagent in combination with trimethylsilyl triflate produces symmetrical ethers from aldehydes without concomitant formation of competitive products.Under similar conditions, PMS reagent failed to provide the expected symmetrical ethers and Friedel-Crafts products were formed.Reduction of quinones to hydroquinones is also described.
- Aizpurua, Jesus M.,Lecea, Begona,Palomo, Claudio
-
p. 2342 - 2347
(2007/10/02)
-
- REAGENTS AND SYNTHETIC METHODS 52. SILANE REDUCTION OF CARBONYL COMPOUNDS IN THE PRESENCE OF IODINE.
-
Synthetic utility of 1,1,3,3,-tetramethyldisiloxane (TMDS) reagent under the influence of iodine is described.TMDS reagent in combination with iodine produces alkyl iodides from carbonyl compounds and oxiranes in good to excellent yields.Reduction of quinones into hydroquinones is also described.The mentioned transformations are explained from mechanistic points of view.
- Lecea, B.,Aizpurua, J. M.,Palomo, C.
-
p. 4657 - 4666
(2007/10/02)
-
- Carbon-Halogen Bonding Studies. Halogen Redistribution Reactions between Alkyl or Acetyl Halides and Tri-n-butyltin Halides
-
The equilibrium positions have been determined for the halogen redistribution reactions of tri-n-butyltin halides with a variety of structurally different types of alkyl halides and with acetyl halides.These have been related through the reaction ΔGo values to carbon-halogen bond dissociation energy differences.It is suggested that the trends observed in the latter may provide evidence for the existence of a small steric bond weakening effect in the order C-I > C-Br > C-Cl bonds on going from methyl to primary, secondary, and tertiary alkyl halides.On the other hand, with the 2,3-? bond containing allyl, benzyl, and propargyl halides , α-haloacetones, and haloacetonitriles, there may be some type of electronic carbon-halogen bond strengthening effect which lies in order C-I > C-Br > C-Cl.Finally, for the acetyl halides, the data are in agreement with increases in bond strengths resulting from ? contributions being in the order C-Cl > C-Br > C-I.
- Friedrich, Edwin C.,Abma, Charles B.
-
p. 1367 - 1371
(2007/10/02)
-
- Sulfonation of aromatic compounds in the presence of solvents
-
A process for the sulfonation of aromatic compounds wherein an aromatic substance consisting of one or more aromatic compounds susceptible to the action of sulfur trioxide is formed into a reactant by admixture with one or more organic liquids, substantially inert to sulfur trioxide under the conditions of the process, which reactant is brought to boiling at a temperature not greater than 100° C under a pressure of from 0.1 mm Hg to atmospheric pressure, gaseous sulfur trioxide is introduced thereinto thereby causing it to continue to boil, the component or components of the reactant thus volatilized is or are reconverted to liquid in a heat-exchanger and recycled to the reaction chamber, and the pressure in the reaction chamber and the rate at which the gaseous sulfur trioxide is introduced into the reactant are controlled so as to ensure that there is always present in the reaction chamber an amount of volatilizable matter exceeding that amount volatilizable by the heat of reaction of the aromatic substance present in the reaction chamber with the gaseous sulfur trioxide in contact with said aromatic substance and that the temperature of the reaction mixture is a temperature of 100° C or below.
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