具有拥挤的 1,8-双（4'-苯胺基）萘模板的立体控制光二聚反应。

Stereocontrolled photodimerization with congested 1,8-bis(4'-anilino)naphthalene templates.

机构信息

Department of Chemistry, Georgetown University, Washington, DC 20057, USA.

出版信息

J Org Chem. 2010 Oct 1;75(19):6653-9. doi: 10.1021/jo101547w.

PMID:20809657

Abstract

Suzuki cross-coupling of a 1,8-dihalonaphthalene with 4-methoxy-3-methylphenylboronic acid or 4-acetamidophenylboronic acid and subsequent functional group transformation gave 1,8-bis(3'-methyl-4'-anilino)naphthalene, 16, and 1,8-bis(4'-anilino)naphthalene, 21, in 65% and 90% overall yield, respectively. These congested compounds exhibit two cofacial aniline rings that favor a proximate, parallel arrangement of covalently attached cinnamoyl units suitable for stereoselective photodimerization. The [2 + 2]cycloaddition was found to proceed with high yield and exclusive formation of cis,trans,cis-cyclobutane-1,2-dicarboxylic acids. Amide formation with cinnamoyl chloride and template 21 followed by photochemical dimerization and acidic hydrolysis gave β-truxinic acid, 10, in 69% overall yield. Coupling of 21 and (E)-3-(3,4-dimethylphenyl)acrylic acid in the presence of EDC, UV irradiation, and cleavage gave cis,trans,cis-3,4-bis(3,4-dimethylphenyl)cyclobutane-1,2-dicarboxylic acid, 26, in 60% yield. In both cases, the template was quantitatively recovered.

摘要

铃木交叉偶联 1,8-二卤代萘与 4-甲氧基-3-甲基苯硼酸或 4-乙酰氨基苯硼酸，随后进行官能团转化，得到 1,8-双（3'-甲基-4'-苯胺基）萘、16 和 1,8-双（4'-苯胺基）萘、21，总收率分别为 65%和 90%。这些拥挤的化合物表现出两个共面的苯胺环，有利于共价连接的肉桂酰基单元的接近、平行排列，适合立体选择性光二聚化。[2+2]环加成反应以高产率进行，并且仅形成顺式、反式、顺式-环丁烷-1,2-二羧酸。与肉桂酰氯和模板 21 形成酰胺，然后进行光化学二聚化和酸性水解，以 69%的总收率得到β-曲酸、10。在 EDC、UV 照射和裂解存在下，将 21 和（E）-3-（3,4-二甲基苯基）丙烯酸偶联，以 60%的产率得到顺式、反式、顺式-3,4-双（3,4-二甲基苯基）环丁烷-1,2-二羧酸、26。在这两种情况下，模板都被定量回收。