23313-43-1Relevant articles and documents
Vicinal Difunctionalization of Alkenes under Iodine(III) Catalysis involving Lewis Base Adducts
Aertker, Kristina,Rama, Raquel J.,Opalach, Julita,Mu?iz, Kilian
supporting information, p. 1290 - 1294 (2017/04/18)
The influence of a 2-pyridinyl substituent on the catalytic performance of aryl iodides as catalyst in iodine(III) chemistry was explored. An efficient Lewis base adduct between the pyridine nitrogen and the electrophilic iodine(III) center was identified and confirmed by X-ray analysis. This arrangement was shown to generate a kinetically competent superior catalyst structure for the catalytic dioxygenation of alkenes. It introduces the concept of Lewis base adduct formation as a kinetic factor in iodine(I/III) catalysis. (Figure presented.).
Synthesis of β-acetoxy alcohols by PhI(OAc)2-mediated metal-free diastereoselective β-acetoxylation of alcohols
Zhao, Chun-Yang,Li, Liang-Gui,Liu, Qing-Rong,Pan, Cheng-Xue,Su, Gui-Fa,Mo, Dong-Liang
, p. 6795 - 6803 (2016/07/23)
β-Acetoxy alcohols can be synthesized in good yields with excellent diastereoselectivity from tertiary alcohols through PhI(OAc)2-mediated metal-free β-acetoxylation. Mechanistic studies showed that the β-acetoxylation process might undergo dehydration and sequential highly regioselective and diastereoseletive dioxygenation. Gram scale and diverse useful scaffolds could be prepared via this β-acetoxylation process.
Metal-free, organocatalytic syn diacetoxylation of alkenes
Zhong, Wenhe,Liu, Shan,Yang, Jun,Meng, Xiangbao,Li, Zhongjun
supporting information; experimental part, p. 3336 - 3339 (2012/08/29)
A novel method for the organocatalytic syn diacetoxylation of alkenes has been developed using aryl iodides as efficient catalysts. A broad range of substrates, including electron-rich as well as electron-deficient alkenes, are smoothly transformed by the new procedure, furnishing the desired products in good to excellent yields with high diastereoselectivity (up to >19:1 dr).
BF3·OEt2-promoted diastereoselective diacetoxylation of alkenes by PhI(OAc)2
Zhong, Wenhe,Yang, Jun,Meng, Xiangbao,Li, Zhongjun
experimental part, p. 9997 - 10004 (2012/02/05)
Selective syn and anti diacetoxylations of alkenes have been achieved using a PhI(OAc)2/BF3·OEt2 system in the presence and absence of water, respectively. A broad range of substrates including electron-deficient alkenes (such as α,β-unsaturated esters) could be elaborated efficiently at room temperature with this methodology, furnishing the desired products in good to excellent yields and diastereoselectivity. In particular, a multigram-scale diastereoselective diacetoxylation of methyl cinnamate (5.00 g) was also accomplished in a few hours, maintaining the same efficiency as small-scale reaction. This novel methodology provides an alternative approach for the preparation of various 1,2-diols.
The nature of the catalytically active species in olefin dioxygenation with PhI(OAc)2: Metal or proton?
Kang, Yan-Biao,Gade, Lutz H.
supporting information; experimental part, p. 3658 - 3667 (2011/05/03)
Evidence for the protiocatalytic nature of the diacetoxylation of alkenes using PhI(OAc)2 as oxidant is presented. Systematic studies into the catalytic activity in the presence of proton-trapping and metal-complexing agents indicate that protons act as catalysts in the reaction. Using triflic acid as catalyst, the selectivity and reaction rate of the conversion is similar or superior to most efficient metal-based catalysts. Metal cations, such as Pd(II) and Cu(II), may interact with the oxidant in the initiation phase of the catalytic transformation; however, 1 equiv of strong acid is produced in the first cycle which then functions as the active catalyst. Based on a kinetic study as well as in situ mass spectrometry, a mechanistic cycle for the proton-catalyzed reaction, which is consistent with all experimental data presented in this work, is proposed.
Chemo-, regio-, and stereoselective synthesis of syn -aryl glycol monoesters from aryl olefins with hydrogen peroxide catalyzed by RuCl 3
Zhang, Yanqiao,Chu, Guobiao,Cui, Xiaoxue,Han, Zhijie,Dou, Daoke,Chen, Yuanli,Yu, Xiaosong,Li, Chunbao
supporting information; experimental part, p. 1118 - 1122 (2010/06/20)
Chemo-, regio-, and stereoselectivity have been achieved in the oxidations of aryl olefins. The aryl olefins were oxidized by 2 equivalents of H 2O2 in acetic acid, catalyzed by 0.02 equivalent of RuCl3, leading to the formations of syn-aryl glycol monoesters. As the reaction is concerted, both the regio- and stereoselectivity are excellent. In the presence of aliphatic C=C bonds, the aryl C=C bonds were selectively dioxygenated. This represents the first example of chemoselective dioxygenation of aryl C=C bonds. Georg Thieme Verlag Stuttgart - New York.
CuI/l-proline-catalyzed selective one-step mono-acylation of styrenes and stilbenes
Prathima, P. Sai,Maheswari, C. Uma,Srinivas,Rao, M. Mohan
supporting information; experimental part, p. 5771 - 5774 (2010/11/05)
Vicinal di-oxygenation of styrene-type olefins was achieved with cheaper, less toxic CuI in the presence of l-proline as ligand and NaIO4 as the oxidant. This approach provides a straightforward and efficient access to mono-acylated diols from both styrene and stilbene derivatives with good to excellent yields and diastereoselectivity.
Palladium-catalyzed olefin dioxygenation
Li, Yang,Song, Datong,Dong, Vy M.
, p. 2962 - 2964 (2008/09/20)
A general method for the vicinal dioxygenation of olefins was developed using cationic Pd diphosphine complexes as the catalysts and PhI(OAc)2 as the terminal oxidant. In comparison to known Pd-catalyzed vicinal oxidations, this method is suitable for a broad range of olefins in both inter- and intramolecular reactions. An 18O-labeling experiment provides insight into the mechanism of this transformation which presumably involves Pd(II)/Pd(IV) intermediates. Copyright
A rapid 1,2-dihydroxylation of alkenes using a lipase and hydrogen peroxide under microwave conditions
Sarma, Kuladip,Borthakur, Naleen,Goswami, Amrit
, p. 6776 - 6778 (2008/02/13)
The combined advantages of using an enzyme immobilized lipase from Pseudomonas sp [PSLG6], hydrogen peroxide, ethyl acetate and microwave irradiation for the dihydroxylation of olefins are reported.
Preparation and Enantiomer Recognition Behaviour of Crown Ethers containing cis-1-Phenylcyclohexane-1,2-diol and trans-1,2-Diphenylcyclohexane-1,2-diol as a Chiral Subunit
Naemura, Koichiro,Miyabe, Hajime,Shingai, Yasuhiro,Tobe, Yoshito
, p. 1073 - 1078 (2007/10/02)
Pig liver esterase-mediated hydrolysis of (+/-)-cis-2-acetoxy-1-phenylcyclohexanol 5 gave (+)-cis-1-phenylcyclohexane-1,2-diol 4 of high optical purity, from which (-)-trans-1,2-diphenylcyclohexane-1,2-diol 8 has been prepared.Using these diols (+)-4 and
