Development of New Organic Reactions by Use of Electron Acceptor Quinones

利用电子受体醌开发新的有机反应

• 批准号: 10650849
• 负责人: OSHIMA Takumi
• 金额: $ 2.24万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650849/
• 关键词: [2+2] photocycloaddition; Homoquinone; Diels-Alder Reaction; Cation Recognition; Regioselectivity; Endo-selectivity; Kinetics; Substituent Effects; ナフトキノン; ジアゾアルカン; 1, 3-双極子付加; 光分解; 熱分解; 6π電子環化; カルベン; ピリドノクラウンエーテル; 光誘起電子移動; 光付加反応; プロトン移動

[2+2] photocycloaddition: Irradiation of various meto- and para-substituted homobenzoquinones with ethyl vinyl ethers gave the [2+2] photoadducts regio- and endo-selectively. The adducts have an antiform built by the addition of ethyl vinyl ethers from the less hindered side of homobenzoquinones. All of the CH_3, Cl, Br, and CH_3O substituents at the reacting C = C double bond afforded head-to-head addition predominantly. In the case of CH_3, Cl, and Br, the ethoxy group was -oriented in the endoposition, while the CH_3O substituent led to a 1/5 mixture with the exo-isomer. It was also found that the Br-substituted [2+2] adducts undergo a facile skeletal rearrangement, being converted into dihydro-obenzoquinone methide for para-substituent and dihydro-o-benzofuran derivatives for meta-substitution, probably under the influence of the in sit generated HBr.Diels-Alder reactions of quinocrown ethers: 15-21-membered auinocrown ethers 1a-c and 18-membered quinobenzocrown ether 1d with cyclo … More pentadiene were catalyzed by the addition of alkali, alkaline earth metal and ammonium perchlorates, and scandium trifluoromethane-sulfonate. The alkali metal ions brought about a fairly selective rate-acceleration for each crown ether due to the size-fitted ion-in-the-hole complexation. However, such a hole-size-selectivity was not observed for the reactions catalyzed by divalent alkalie earth (Mg^<2+> to Ba^<2+>) and trivalent Sc^<3+> ions. The wrapping complexation played a significant role in rate-acceleration in such a way that the smallest Mg^<2+> caused 160 times rate-enhancement for the most flexible 1c and the Sc^<3+> performed maximal 3700 times rate-increment for the 18-membered quinobenzocrown 1d. These effects of cation recognition were rationalized by the reduction of LUMO energy that is favored by the orbital interaction with the HOMO of cyclopentadiene. The magnitude of rate-enhancement was expained in terms of the cation binding affinity and coordination geometry of quinocrown ethers as well as the valence of cations. Less

[2+2]光环加成反应：各种间位和对位取代的高对苯二酚与乙基乙烯基醚反应，得到区域和内选择性的[2+2]光加成产物。加合物具有通过从高对苯二酚较少受阻的一侧添加乙基乙烯基醚而构建的反形式。反应中的C=C双键上的所有CH3、Cl、Br和CH3O取代基均以头对头加成反应为主。在CH3、Cl和Br3种异构体中，乙氧基位于内位，而CH3O取代基与外异构体形成1/5的混合物。研究还发现，二溴取代的[2+2]加合物发生了简单的骨架重排，转化为二氢苯醌甲醚的对位取代基和二氢邻苯并呋喃的间位取代衍生物，可能是受In SIT生成的HBr.五元冠醚的Diels-Alder反应：15-21元的冠醚1a-c和18元的喹苯并冠醚1d与环…碱、碱土金属和高氯酸铵以及三氟甲烷磺酸钪的加入使戊二烯的催化活性增加。碱金属离子对每个冠醚都有较好的选择性加速作用，这是由于配合离子的孔道络合作用所致。然而，对于二价碱土(Mg^&lt；2+&gt；到Ba^&lt；2+&gt；)和三价Sc^&lt；3+&gt；离子催化的反应，没有观察到这样的孔尺寸选择性。包合作用显著，最小的Mg^lt；2+对最柔韧的1c有160倍的速率提高，而Sc^lt；3+&gt；对18元的喹苯并冠醚1D有最大的3700倍的速率提高。这些阳离子识别效应被环戊二烯与HOMO的轨道相互作用有利于LUMO能量的降低所合理化。根据五元杂环醚的阳离子结合亲和力和配位几何构型以及阳离子的价态解释了速率提高的大小。较少

项目成果

K.Kokubo: "Conformational specificity in photoinduced intramolecular 1,7-hydrogen abstraction of homonaphthoquinones having spiro-linked dibenzocycloheptene ring"Org.Lett.. vol.2(in press). (2000)

K.Kokubo：“具有螺连接的二苯并环庚烯环的同萘醌的光诱导分子内 1,7-氢提取中的构象特异性”Org.Lett.. vol.2（出版中）。

T. Oshima: "Selective cation binding of crown ether acetals in electrospray ionization mass spectrometry"J. Chem. Soc., Perkin Trans.. 2. 145-145 (1998)

T. Oshima：“电喷雾电离质谱中冠醚缩醛的选择性阳离子结合”J。

T. Oshima: "Kinetic study of thermolysis of diarylhomoquinones"Endo/exo substituent and solvent effects, J. Chem. Soc., Perkin Trans.. 2. 135-135 (2000)

T. Oshima：“二芳基高醌热解的动力学研究”Endo/exo 取代基和溶剂效应，J. Chem。

K. Kokubo: "Steric effects in photoinduced electrcn transfer reaction of halogenated 1,4-benzoquinones with donor olefins"Org. Lett.. Vol. 2. 1979-1979 (2000)

K. Kokubo：“卤代 1,4-苯醌与供体烯烃的光诱导电子转移反应中的空间效应”Org。

K. Kokubo: "Regio- and endo-selective [2+2] photocycloadditions of homobenzoquinones with ethyl vinyl ether"J. Org. Soc.. Vol. 65. 3371-3371 (2000)

K. Kokubo：“高苯醌与乙基乙烯基醚的区域选择性和内选择性 [2 2] 光环加成”J。