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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Cyclic tetramer of a metalloporphyrin based on a quadruple hydrogen bond
Haruki Ohkawa1, Akihiro Takayama, Satoshi Nakajima
1Consolidated Research Institute for Advanced Science and Medical Care, Waseda University (ASMeW), Shinjuku, Tokyo, Japan.
Abstract:
[reaction: see text] This paper describes the selective formation of a cyclic tetramer from a readily synthesized metalloporphyrin with two self-complementary quadruple hydrogen-bonding units. The extremely strong quadruple hydrogen-bonding unit, 2-ureido-4[1H]-pyrimidinone, enabled the formation of a stable cyclic tetramer based on a tetraphenylporphyrin derivative over a wide concentration range. This hydrogen-bonded tetramer is a new functional unit for use in a higher-ordered architecture of a supramolecular porphyrin assembly.
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