High-Pressure Access to the Δ<sup>9</sup>-<i>cis</i>- and Δ<sup>9</sup>-<i>trans-</i>Tetrahydrocannabinols Family
作者:Lucio Minuti、Eleonora Ballerini
DOI:10.1021/jo200796b
日期:2011.7.1
Diels–Alderreactions of a range of 1-(alkoxy/alkyl-substituted phenyl)buta-1,3-dienes with methyl vinyl ketone and methyl acrylate carried out in ethanol as the reaction medium under 9 kbar pressure were investigated. The use of high pressure as the activating method of the Diels–Alderreactions allows the efficient and endodiastereoselective generation of a series of cis-cyclohexenyl-benzene cycloadducts
研究了1-(烷氧基/烷基取代的苯基)丁1,3-二烯与甲基乙烯基酮和丙烯酸甲酯在9 kbar压力下的乙醇中作为Diels-Alder反应的反应介质。使用高压作为Diels-Alder反应的活化方法,可以高效,内非对映选择性地生成一系列顺式-环己烯基-苯环加合物,并选择性地转化为其反式-末端。所产生的顺式-环己烯基-苯和反式-环己烯基-苯是用于获得取代的特权顺式-6a,7、8、10a-四氢-6 H-苯并[ c ]苯并二甲苯的有用前体。反式-6a,7,8,10a-四氢-6 H-苯并[ c ]亚甲基骨架。Δ的全合成9 -顺四氢大麻酚(THC)和Δ 9 -反-THC,通过使用选择的狄尔斯-阿德耳加合物,中有描述。最后,为了获得Δ路线9 -反式中基于(对映异构体二者纯形式-THC小号) - ( - ) - 1-氨基-2-(甲氧基甲基)(SAMP)也报道吡咯烷腙方法。
High-Pressure Diels−Alder Cycloadditions between Benzylideneacetones and 1,3-Butadienes: Application to the Synthesis of (<i>R,R</i>)-(−)- and (<i>S,S</i>)-(+)-Δ<sup>8</sup>-Tetrahydrocannabinol
combination with the mild Lewis acid HfCl4·2THF allows these reactions to efficiently and regioselectively produce a series of ortho-substituted cyclohexenyl-benzene cycloadducts, that are useful precursors for the expeditious construction of the privileged 6,6-dimethyltetrahydro-6H-benzo[c]chromene skeleton. Application to the synthesis of Δ8-trans-THC in both enantiomericpure forms is based on the successful
据报道,各种烷氧基/烷基取代的亚苄基丙酮与甲基-1,3-丁二烯的高压Diels-Alder反应。高压(8-11 kbar)与温和的路易斯酸HfCl 4 ·2THF结合活化使这些反应有效和区域选择性地产生了一系列邻位取代的环己烯基-苯环加合物,它们对于快速构建环己烯基有用的前体。特权的6,6-二甲基四氢-6 H-苯并[ c ]亚甲基骨架。到Δ的合成应用8 -反式-THC在两种对映体纯的形式是基于由SAMP -腙的方法选择环加成的成功解决。
Aldol Condensation of Aldehydes with Ketones Promoted by the Copper(II) Ion. Orientation to the Chemical Model for Metalloaldolases
作者:Masaaki Iwata、Sakae Emoto
DOI:10.1246/bcsj.49.1369
日期:1976.5
condensation reactions of aromaticaldehydes such as 1 through 4 and 7 through 13, and aliphatic aldehydes such as 5 and 6, with a number of ketones promoted by the copper(II) ion were examined. The reactions were specifically promoted by the copper(II) ion, while such metal ions as zinc, cobalt(II), manganese(II), and magnesium were quite inactive as catalysts. All the aldehydes but 7 and 8 reacted with
研究了芳香醛(例如 1 到 4 和 7 到 13)和脂肪醛(例如 5 和 6)与许多由铜 (II) 离子促进的酮的羟醛缩合反应。铜 (II) 离子特别促进了反应,而锌、钴 (II)、锰 (II) 和镁等金属离子作为催化剂非常不活泼。在 Claisen-Schmidt 类型的反应中,除 7 和 8 之外的所有醛都与除乙酰乙酸乙酯、乙腈和硝基甲烷以外的所有脂肪族酮反应不同程度。乙酰丙酮得到Knoevenagel类型的缩合产物。在醛与 2-丁酮的反应中,醛会区域特异性地攻击 2-丁酮 C3 处的亚甲基。胺类抑制反应,同时观察到锌或钴 (II) 的共存效应。结果表明,在铜(II)离子促进的反应中,存在的底物选择性很大程度上取决于酮的种类。结果,可能...
Organocatalytic enantio- and diastereoselective synthesis of 3,5-disubstituted prolines
作者:Iker Riaño、Estibaliz Díaz、Uxue Uria、Efraím Reyes、Luisa Carrillo、Jose L. Vicario
DOI:10.1039/c5cc09329e
日期:——
The asymmetric synthesis of substituted pyrrolidines has been accomplished using a novel organocatalytic cyclization reaction promoted by aCinchonaalkaloid base primary amine.
Initially, it was confirmed that the substituting the α,β-unsaturated ketone with pent-1,4-diene-3-one as a linker group significantly reduced the cytotoxicity of the final compounds. Subsequently, the penta-1,4-dien-3-one group was utilized as a privileged fragment for further structural optimization. Following two subsequent rounds of optimizations, we identified compound IIB-2, which contains a 2,6-dimethoxyphenyl-