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91.
Ahmed A. Hasanein Samir A. Senior 《International journal of quantum chemistry》2011,111(15):3993-4010
Amine‐Imine tautomerization in 2‐amino‐pyrimidine (I), 2‐amino‐4,6‐dichloropyrimidine (II), 2‐amino‐4,6‐dimethylpyrimidine (III), and 2‐amino‐4,6‐dimethoxypyrimidine (IV) and their 1:1 and 1:2 H‐bonded complexes with water have been studied using the B3LYP/6‐31++G** method. Optimum molecular geometries, electronic properties, and energetics of these systems have been discussed. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
92.
93.
以苯乙酰基四羰基钴作为催化剂,研究了对芳香醛亚胺与一氧化碳(CO)的交替共聚反应.采用6种芳香醛亚胺单体,分别与CO进行交替共聚反应,得到了6种新的多肽类聚合物.利用核磁共振谱、红外光谱、凝胶渗透色谱(GPC)及MALDI-TOF质谱等对聚合物的结构进行了表征.探讨了芳香醛亚胺苯环上取代基的位阻效应和电子效应对聚合反应的影响.结果表明,聚合物链终止端存在3种不同类型的端基,分别具有慕尼黑酮类结构、咪唑啉类结构以及酰胺类结构,对这些端基的形成机理进行了讨论. 相似文献
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95.
Maddimsetti Venkateswara Rao Annavareddi NareshGudipati Saketh Batchu Venkateswara Rao 《Tetrahedron letters》2013
A formal synthesis of dysiherbaine was achieved from d-mannitol using Grignard addition on chiral imine, RCM and Michael addition as key steps. 相似文献
96.
Abstract Two 36-membered (2+2) Schiff-base macrocycles have been prepared and characterised without the use of template ions or high dilution techniques. Rather, intramolecular hydrogen-bonding and π-π interactions promote the isolation of these “figure-of-eight” products in good yields. Two cobalt(III) complexes of the 18-membered (1+1) Schiff-base macrocycles are formed when cobalt(II) is used as a template. The structures of one “figure-of-eight' metal-free (2+2) macrocycle and of one dicobalt(III) complex of a (1+1) macrocycle, in which the cobalt centres are octahedral, are presented. [H4L1tBu]2: C70H70N8O9, space group P-1, a=7.747(1), b=17.106(3), c=23.662(4) å, α=104.83(3), β=95.86(3), γ=97.80(3)°, U=2972.4(8) å3, Z=2, Dc=1.30 g cm?3, T=100K, 554 parameters, R1=0.072 [for 4137 reflections having F>4[(F)], wR2=0.191 and goodness of fit 0.97 (for all 8343 independent F2 data). [Co2(L1tBu)(OAc)2(pyridine)] 1.5DMF 0.5MeCN, C47.5H49N7O9.5Co2, space group P2(1)/n, a=13.067(2), b=26.071(4), c=14.023(3) å, β=93.02(1)°, U=4770.6(15) å3, Z=4, Dc=1.38 g cm?3, T=168 K, 622 parameters, R1=0.075 [for 5233 reflections having F > 4[?F?], wR2=0.133 and good ness of fit 1.08 (for all 8512 independent F2 data). 相似文献
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98.
Sucheta Kudrimoti 《Tetrahedron letters》2005,46(7):1209-1210
A novel solvent-free, one-pot synthesis of α-aminophosphonates in the presence of catalytic (bromodimethyl)sulfonium bromide at room temperature in high yields is reported. 相似文献
99.
Potassium alkynyltrifluoroborates and potassium (2-phenyl)vinyltrifluoroborates react with N-3-butenyl-(2,2-dichloro-1-propylidene)amine in the presence of BF3·Et2O as a Lewis acid to synthesize rearranged Mannich products. The reaction starts with a cationic 2-aza-Cope rearrangement of the imine, followed by the Lewis acid promoted borono-Mannich-type reaction on the rearranged imine to result in a new class of functionalized N-homoallylamines. 相似文献
100.
Ke Wu Quanxin Li Wenbo Su Prof. Dr. Shaofei Ni Prof. Dr. Qingfa Zhou 《Angewandte Chemie (International ed. in English)》2023,62(51):e202314191
A new phosphine-catalyzed reaction of α-substituted allenes with aryl imines, in stark contrast to classic cycloaddition reactions, has been developed. This reaction delivers valuable highly functionalized itaconimides with excellent stereoselectivities by a new «un-cyclizing» reaction mode involving β′-carbon of α-substituted allenes. Moreover, the present «un-cyclizing» reaction can also be carried out in a one-pot fashion and scaled up to the gram scale by using aryl aldehydes, without the need to isolate the aryl imines. Mechanistic studies and control experiments reveal the crucial role of H2CO3 for the present reaction mode. In addition, density functional theory (DFT) calculations were performed to understand the possible mechanism. 相似文献