Catalytic Enantioselective Desymmetrization of Norbornenoquinones via C(sp<sup>2</sup>)–H Alkylation
作者:Rahul Sarkar、Santanu Mukherjee
DOI:10.1021/acs.orglett.6b03168
日期:2016.12.2
The enantioselective Diels–Alder (DA) reaction with monosubstituted p-benzoquinones is an unmet challenge. A new approach for the enantioselective synthesis of monosubstituted quinone-DA adducts is presented based on C(sp2)–H alkylative desymmetrization of meso-DA adducts. Catalyzed by a tertiary amino-thiourea derivative, this reaction utilizes nitroalkanes as the alkylating agents and generates densely
Diels–Alder reactions between cyclopentadiene analogs and benzoquinone in water and their application in the synthesis of polycyclic cage compounds
作者:Yijun Shi、Xuejing Liu、Ying Han、Peng Yan、Fusheng Bie、Han Cao
DOI:10.1039/c9ra09745g
日期:——
Diels–Alder reactions between cyclopentadiene analogs and p-benzoquinone were explored in water and yielded 83–97% product, higher than the results reported in water with a catalyst or cetrimonium bromide (CTAB) micelles. The novel adduct 10 was synthesized and further used to synthesize the bi-cage hydrocarbon 4,4′-spirobi[pentacyclo[5.4.0.02,6.03,10.05,9]undecane], which has a high density (1.2663
在水中探索了环戊二烯类似物和对苯醌之间的 Diels-Alder 反应,并产生了 83-97% 的产物,高于使用催化剂或溴化西曲铵 (CTAB) 胶束在水中报道的结果。合成了新型加合物10 ,并进一步用于合成具有高密度的双笼烃 4,4'-螺双[五环[5.4.0.0 2,6 .0 3,10 .0 5,9 ]十一烷] (1.2663 g cm -3)和高体积燃烧热(53.353 MJ L -1)。使用该方法从 2,2'-双(对苯醌)和环戊二烯类似物开始,在水中合成了四种新型双笼烃化合物。
Catalytic Enantioselective
<i>de novo</i>
Construction of Chiral Arenes through Desymmetrizing Oxidative [4+2]‐Cycloaddition
A desymmetrization approach to centrally chiral unfunctionalized arenes is developed through the enantioselective de novo construction of the arene ring by oxidative [4+2]-cycloaddition of polycyclic meso-cyclohexenediones. Catalyzed by a diphenylprolinol silyl ether, this external oxidant-free protocol gives rise to diversely substituted chiral arenes with outstanding enantioselectivity (up to >99
Synthesis, characterization and crystal density modeling of spiropolycyclic oxiranes
作者:Alan P Marchand、Rajesh Shukla、Paul R.J Davey、Herman L Ammon、Zuyue Du、Simon G Bott
DOI:10.1016/s0040-4020(98)00165-3
日期:1998.4
and bis-epoxides 1–6 have been synthesized. The structures of 1–6 have been established unequivocally via application of single crystal X-ray crystallographic methods. The crystaldensities of 1–6 (from X-ray crystallographic data) are compared with the results of density predictions.
Singh, Vishwakarma; Raju, Bhupathiraju N. S., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1996, vol. 35, # 4, p. 303 - 311