Synthesis of Polyglycerol, Porphyrin-Cored Dendrimers Using Click Chemistry

✍ Scribed by Elmer, Stephanie L. (author);Man, Sonny (author);Zimmerman, Steven C. (author)

• Book ID: 102828447
• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 525 KB
• Volume: 2008
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200800401

✦ Synopsis

Abstract

Polyglycerol, porphyrin‐cored dendrimers were synthesized by the click reaction of azide‐cored polyglycerol dendrons and octa‐alkynylporphyrin 19. The dendrons were synthesized divergently starting with TBDPS‐protected allyl alcohol 2. Two, three and four cycles of dihydroxylation‐allyl etherification gave dendrons [G‐2.5] 6, [G‐3.5] 8, [G‐4.5] 11, with four, eight, and sixteen alkene groups, respectively. Dendron 11 was readily prepared on large scale with an overall yield of 45 %. Dendron 8 was deprotected and converted into the corresponding alkyne – and azide‐cored dendron 13 and 15 in 89 % and 75 % yield, respectively. Dendron 11 was deprotected and converted into the corresponding alkyne – and azide‐cored dendron 16 and 18 in 68 % and 24 % yield, respectively. Both the [G‐3.5]‐azide 15 and [G‐4.5]‐azide 18 were separately “clicked” to polyalkyne core 19 via theHuisgen 1,3‐dipolar cycloaddition to afford 20 and 21 in 65 % and 66 % yield, respectively. Dendrimer 21 has a MW of ca. 16000 and 128 peripheral alkene groups. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)