化学
对映选择合成
磷酸
催化作用
分子内力
Diels-Alder反应
布朗斯特德-洛瑞酸碱理论
药物化学
有机化学
手性(物理)
立体化学
手征对称破缺
物理
量子力学
Nambu–Jona Lasinio模型
夸克
作者
Norie Momiyama,Tohru Konno,Yuichi Furiya,Takeaki Iwamoto,Masahiro Terada
摘要
Chiral bis-phosphoric acid 1 was designed to identify a new class of structural features in chiral Brønsted acid catalysts. X-ray diffraction analysis revealed the single atropisomer 1, bearing S axial chirality at 3,3′-biaryl substituents on (R)-binaphthyl and intramolecular hydrogen bonding between the two phosphoric acid moieties. The newly designed bis-phosphoric acid 1 was evaluated in the Diels–Alder reaction of α,β-unsaturated aldehydes 4 with 1-N-acylamino-1,3-butadienes 3. After systematic variation of the catalyst substituents, as well as the N-acyl substituents of 1,3-butadiene, the use of an N-Cbz amidodiene 3a in the presence of bis-phosphoric acid 1e with a 2,4,6-tri-isopropylphenyl group was found to be optimal to yield the 1S,6R enantiomeric product 5aa in a Diels–Alder reaction of acrolein (4a). Application of this method to substituted substrates was found to be an efficient approach to the enantioselective synthesis of 3- and 3,6-substituted cyclic formylcarbamates 5. The specific character as well as the utility of 1e was further established by comparing its enantioselectivity, absolute stereochemistry, and catalytic efficiency with those of mono-phosphoric acid 2.
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