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Research Projects Below is a sampling of several research projects that are currently active. Rhenium Tripod Compounds We are currently examining the chemistry of a variety of tripod ligands. For example have prepared tris(pyrazolyl)methane and used it to make the previously reported compound [Re(CO)3(tpm)]Br.
We are investigating the potential of technetium compounds in this class to act as diagnostic imaging agents. This is a new and active area in our group. Group 6 pyca chemistry Pyridine-2- carboxaldehyde plus amino esters give conjugated Schiff Base compounds. We have made several Group 6 derivatives and published our results. (J.Organomet. Chem. 589, 29, 1999.) Currently we are looking at using a diammine (N-methyl ethylenediamine. The pendant secondary amino group will be tested for the preparation of peptide bonds using the COOH end of amino acids. Below is the recently obtained crystal structure of W(CO)4(pyca-CH2CH2NMe). These compounds have the typical solvatochromic behavior seen for metal diimine compounds. The crystal structure of the molybdenum -ß-alanine-OEt tetracarbonyl derivative - Mo(CO)4(pyca-ß-ala-OEt) - is shown below.
Pd and Pt pyca chemistry We have used the pyca ligand structure to prepare Pd and Pt compounds also. We have discovered that using long chain amino acids (a,w)-amino acids gives linear structures. See below.
We are currently exploring the properties of these compounds. N-Confused Tetraphenyl porphyrin Porphyrin (NCTPP) Chemistry Recently workers have discovered that analogs of tetraphenylporphyrin could be made with a pyrrole carbon and pyrrole nitrogen exchanging places. In conjunction with Prof. Chris Ziegler we have made and structurally analyzed the new isostructural compounds, Mo(TPP)(pip)2 and Mo(NCTPP)(pip)2 . Below is the structure of Mo(NCTPP)(pip)2 showing that the Mo is bound to 3 N's and 1 C. It is isostructural with Mo(TPP)(pip)2. An account of this work has been published. (Chemical Communications, 2005 Advance Article DOI: 10.1039/b508913a). Research is continuing as we try to attach new metals to the N-confused porphyrin, study the properties of the compounds and attach biomolecules.
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| Department of Chemistry | College of the Holy Cross | 1 College Street, Worcester, MA 01610 | (508) 793 2490 | email | rherrick@holycross.edu |
