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11.
The intramolecular hydroacylation of 1,2-disubstituted alkenes was considered to be a challenging task due to the side reactions resulted from the lack of additional substituent at 1-position and the low activity caused by the steric hindrance of substituent at 2-position, and an asymmetric version has not been considered possible due to problems associated with the racemization of the products. We have partially solved these problems. Catalyzed by an activated diphosphine-Rh complex and reacted in a selected dihalogenated solvent, the intramolecular hydroacylation of o-(2-arylvinyl)benzaldehydes provided the corresponding 2-aryl-1-indanones in high yields, and its asymmetric variant using o-(2-alkylvinyl)benzaldehydes afforded chiral 2-alkyl-1-indanones in high yields and with moderate enantioselectivities. 相似文献
12.
《Journal of Saudi Chemical Society》2022,26(3):101483
Alkenyl boron-esters and acrylonitrile groups are key structural functional groups found in dyes, pesticides, fluorescent compounds, functional materials, and biologically active drugs. Considerable efforts have been devoted for the introduction of boron-esters and acrylonitrile groups by using alkenes and alkynes conversion routes for boronation, hydroboronation, dehydrogenative boronation, cyanation, hydrocyanation, alkylcyanation, cyanomethylation. These reported methodologies are very valuable for the industrial production of acrylonitriles and alkenyl boron esters. 相似文献
13.
《合成通讯》2013,43(24):4477-4482
Abstract Regioselective synthesis of α‐iodoacetates from alkenes, ammonium acetate, and iodine in acetic acid is reported. The reaction is facile, fast, environmentally, friendly, and cost effective. α‐Iodoacetates are obtained from both acyclic and cyclic alkenes in high yields ranging from 80–95% within 10–20 min. 相似文献
14.
A mild, efficient, and highly regio- and stereoselective method for the methoxy and ethoxy bromination of olefins has been developed using NH4Br as a bromine source and Oxone as an oxidant. Various kinds of olefins (aromatic, linear, and cyclic olefins) afforded the corresponding alkoxy brominated products in moderate to excellent yields. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.] 相似文献
15.
16.
A Cu(OAc)2/DDQ/DTBP/Py system catalyzed oxidative dehydrogenative silylation‐alkenation tandem reaction of readily available alkyl aromatic compounds with silanes was established. A variety of functionalized alkenyl organosilicon compounds were provided in good to high yields with a total β‐(E) selectivity. The control experiments revealed that the transformation might proceed through a radical pathway. 相似文献
17.
The preliminary results of the hydroformylation of 2-phenylsulfonyl substituted norbornene and norbornadiene derivatives catalyzed by the unmodified Rh(CO)2acac system are presented. The reaction, occurring under standard oxo conditions, gives polyfunctionalized exo norbornene- and exo norbornanecarboxaldehydes. The effect of the phenylsulfonyl group has been evaluated: it has been found that the steric properties of the sulfonyl substituent, more than the electronic ones, influence the regioselectivity of the process. 相似文献
18.
二氯二茂锆同异丁基格氏试剂以1:2摩尔比反应,于室温下生成有机锆中间体,后者同烯烃、炔烃或二烯反应,最后生成还原的二聚物或分子内环化产物。 相似文献
19.
Jii Sicher 《Angewandte Chemie (International ed. in English)》1972,11(3):200-214
Earlier evidence led to the view that in bimolecular olefin-forming eliminations the anti steric course is generally preferred over the syn. Recent experiments, however, show that in some common bimolecular elimination reactions, notably those involving onium bases, syn- and anti-eliminations proceed side by side, the former preferentially leading to the trans- and the latter to the cis-olefins. 相似文献
20.
Francesco P. Ballistreri Lucia Brinchi Raimondo Germani Gianfranco Savelli Gaetano A. Tomaselli Rosa M. Toscano 《Tetrahedron》2008,64(44):10239-10243
An aqueous reaction medium, based on a surfactant solution of diethyltetradecylamine N-oxide (AOE-14), was developed for the enantioselective epoxidation of 1,2-dihydronaphthalene and of various cis-β-alkyl styrenes with increasing hydrophobicity, using bleach as oxidant and the Jacobsen chiral (salen)Mn(III) as catalyst. AOE-14 is able to both solubilize all reactants in water and bind the metal of the salen complex acting as coligand. Its use leads to good yields (>75%) and to ee values ranging from 75% up to 91% even in the case of cis-β-alkyl styrenes where lower cis/trans epoxide ratios are observed. The ratio of surfactant/substrate used is 1:1 or 4:1, much lower than those generally used in the literature. 相似文献