Regioselective syntheses and structural characterizations of 2,3-dibromo-and 2,3,7,8,12,13-hexabromo-5,10,15,20-tetraphenylporphyrins

被引：75

作者：

Jaquinod, L ^{[1
]}

Khoury, RG ^{[1
]}

Shea, KM ^{[1
]}

Smith, KM ^{[1
]}

机构：

[1] Univ Calif Davis, Dept Chem, Davis, CA 95616 USA

来源：

TETRAHEDRON | 1999年 / 55卷 / 46期

关键词：

bromination; cyanation; electrophilic substitution; nitroporphyrins; regioselectivity;

D O I：

10.1016/S0040-4020(99)00811-X

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The title dibromoporphyrins 4/5 and hexabromoporphyrins 11/12 are prepared from H-2(2-NO2TPP) 1 and Cu(2-NO2TPP) 8, respectively. The beta-nitro group confines the 18-pi-annulene system of a tetraphenylporphyrin to its N22H-N24H aromatic delocalization pathway which induces the localization of an antipodal double bond on the porphyrin periphery and enhances its susceptibility to electrophilic attack. Dibromination of H-2(2-NO2TPP) 1 occurs regioselectively affording the 12,13-dibromo-2-nitroporphyrin 2 which, upon Michael addition of NaBH4 and re-aromatization of the resulting nitrochlorin 3, provides an entry to 2,3-dibromoTPP 4/5 as well as an improved route to 2,3-dicyanoporphyrins 6/7. Perbromination of Cu(2-NO2TPP) 8 and denitration of 9 gave, after demetalation, 2,3,7,8,12,13-hexabromoTPP 12. Both 4 and 12 are structurally characterized by X-ray crystallography. (C) 1999 Elsevier Science Ltd. AU rights reserved.

引用

页码：13151 / 13158

页数：8

共 34 条

[1] SYNTHESIS OF BETA-SUBSTITUTED PORPHYRINS USING PALLADIUM-CATALYZED REACTIONS [J].