Luis Avila avila@chem.columbia.edu Room: Chandler 455 Phone #: (212)854-8587 1 What Does a Chemist Do? What is Chemistry? “Take white lead, one part, and any glass youthe choose, two parts, fuse together • Studies atomic composition and structural features ofin a substances. crucible and then pour the mixture. To this crystal add the urine an ass and • Investigates the varied interactions amongof substances after forty days you will find emeralds” • Utilizes natural substances and creates artificial ones. • Comprehends theThe complex chemistry living organisms. Stillman, J. M. story of Alchemy andof Early Modern Chemistry; Dover: New York 1960, p. 160. • Provides a molecular interpretation of health and disease. 2 How Does She/He do it? Main Divisions of Chemistry Organic Chemistry Inorganic Chemistry Materials Chemistry Physical Chemistry Analytical Chemistry Industrial Chemistry (Chemical Engineering and Applied Chemistry) Environmental Chemistry Forensic Chemistry Biochemistry 3 What is Organic Chemistry? Largest area of specialization among the various fields of chemistry Synthetic Organic Chemistry Pharmaceutical Chemistry Polymer Chemistry Dye and Textile Chemistry Pulp and Paper Chemistry Agricultural Chemistry Formulation Chemistry (paint, food, petroleum products, adhesives, etc.) Physical Organic Chemistry Correlates the physical and chemical properties of compounds with their structural features. 4 We are interested in the multistep synthesis of natural products, as well as the development of new methodology, particularly to address problems of regio- or stereocontrol. At present (1999), we are working on problems suggested by structures such as those of germine, taxol, cardenolides and codeine Synthetic Organic Chemist: Professor Gilbert Stork 5 2-acetylnerifolin (class Cardenolide) Natural Product with Antitumor Activity Taxol Natural Product with Antitumor Activity6 Synthetic Organic Chemist / Bioorganic Chemist: Professor Samuel Danishefsky Among our areas of current interest in the anticancer field are epothilone and eleutherobin. While structurally diverse, these two compounds seem to function by a taxol-like mechanism in their ability to inhibit microtubule disassembly. Several projects are addressed to goal systems with immunochemical implications. Here we are particularly concerned with the construction of a carbohydratebased tumor antigen vaccine. 7 We deal with structural aspects of bioactive compounds and elucidation of their mode of action. In most cases this involves investigating the interaction of small molecules with their biopolymeric receptors. The recent dramatic advancement in isolation, purification and microspectroscopic methods has made it possible for chemists to become involved in such studies on a molecular structural basis Natural Products Chemist : Professor Koji Nakanishi 8 We view the photon as a reagent for initiating photoreactions and as a product of the deactivation of electronically excited molecules. Our group is developing a novel field termed "supramolecular" photochemistry, or photochemistry beyond the conventional intellectual and scientific constraints implied by the term "molecule". In supramolecular processes non-covalent bonds between molecules play a role analogous to that of covalent bonds between atoms. Physical Organic Chemist / Photochemist Material Chemist: Professor Nicholas Turro 9 What is Inorganic Chemistry? Deals with the properties of elements ranging from metals to non metals • Organometallic Chemistry • Bioinorganic Chemistry • Ceramics and Glass • Semiconductors 10 We have a continuing interest in exploring unusual artifacts resulting from X-ray diffraction experiments (e.g. "bond stretch" isomerism) One of our interests is concerned with compounds with metal-ligand multiple bonds, which are species of considerable current interest in terms of both their bonding and reactivity. Organometallic Chemist / X-ray Spectroscopist: Professor Gerard Parkin 11 In our major effort we are trying to prepare artificial enzymes that can imitate the function of natural enzymes. Bio-organic Chemist : Professor Ronald Breslow A related study involves the synthesis of mimics of antibodies or of biological receptor sites, constructing molecules that will bind to polypeptides with sequence selectivity in water, using mainly hydrophobic interactions. These could be very useful in modulating the activity of peptide hormones, for instance. 12 What is Physical Chemistry? Measures, correlates, and explains the quantitative aspects of chemical processes Theoretical Chemistry Devoted to Quantum and Statistical Mechanics. Theoretical chemists use computers to help them solve complicated mathematical equations that simulate specific chemical processes. Chemical Thermodynamics Deals with the relationship between heat, work, temperature, and energy of Chemical systems. Chemical Kinetics Seeks to measure and understand the rates of chemical reactions. 13 Physical Chemistry Electrochemistry Investigates the interrelationship between electric current and chemical change. Photochemistry, Spectroscopy Uses radiation energy to probe and induce change within matter. Surface Chemistry Examines the properties of chemical surfaces, using instruments that can provide a chemical profile of such surfaces. 14 My research is concerned with structural and dynamic processes in condensed phase systems and biomacromolecular systems. Because the systems studied are often complex many-body systems, it is necessary to utilize the powerful analytical methods of statistical mechanics as well as state-of-the-art methods of computer simulation involving molecular dynamics and Monte Carlo techniques. Theoretical Chemist: Professor Bruce Berne 15 Materials Chemist: Professor Louis Brus My research is materials, surfaces and nanocrystals, especially in relation to optical and electronic properties. This work can include theoretical modeling, experimental chemical physics, and synthetic chemistry. We try to understand the evolution of solid state properties from molecular properties, and to create new materials with nanoscale structure by both kinetic and thermodynamic self-assembly methods. 16 Materials Chemist / Near Field Microscopist Professor David Adams Our research program involves the design, synthesis, and detailed physical investigation of novel molecular and nanoparticle materials which display unique self-organized hierarchical structures and specific optical, electronic, and/or magnetic properties. Emphasis is placed on materials with potential applications in light-emitting devices, optical memory devices, molecular level and single particle level switching devices, and chemosensory devices. Our research is necessarily interdisciplinary where students and post-doctoral researchers are exposed to modern aspects of inorganic, physical, and materials chemistry. 17 Experimental Physical Chemist / Surface Chemist Professor George Flynn We investigate molecular collisions that lead either to chemical reaction or to the exchange of energy between molecules. In particular, we have developed the infrared diode laser absorption probe technique to investigate collisions between molecules. We also study the structure of molecules adsorbed on surfaces by using the Scanning Tunneling Microscope (STM). 18 What is Analytical Chemistry? QUALITATIVE ANALYSIS deals with the detection of elements or compounds (analytes) in different materials. QUANTITATIVE ANALYSIS refers to the measurement of the actual amounts of the analyte present in the material investigated. Chemical and Biochemical Methods •Gravimetry •Titrimetric Analysis •Enzymic Analysis •Inmunochemical Analysis 19 Analytical Chemistry Atomic and Molecular Spectroscopic Methods •Nuclear Magnetic Resonance (NMR) •Electron Spin Resonance (ESR) •Mass Spectrometry (MS) •Vibrational Spectroscopy (IR, RAMAN) •X-Ray Fluorescence Analysis (XPS) •Electronic Spectroscopy (UV, VIS, Luminiscence) •Atomic Spectroscopy (AA, ICP) •Rotational Spectroscopy (Microwave, FIR) 20 Analytical Chemistry • Chromatographic Methods (Partition equilibrium) •Gas Chromatography (GC) •High Performance Liquid Chromatography (HPLC) •Gel Permeation Chromatography (GPC) •Thin Layer Chromatography (TLC) •Ion Chromatography 21 Analytical Chemistry Thermal Methods •Thermogravimetry (TG) •Differential Thermal Analysis (DTA) •Differential Scanning Calorimetry (DSC) •Thermomechanic Analysis (TMA) Electrochemical Methods •Electrogravimetry •Electrophoresis •Conductimetry,Potentiometry •Polarography •Voltammetry 22 We study enzyme mechanisms using NMR. A variety of experiments allow us to probe structural details,dynamics or chemical details such as protonation states. In photosynthetic reaction centers, light energy is converted to chemical potential energy through long-range electron transfer events. A wealth of crystallographic, mutagenic, and spectroscopic work on these centers still leaves important mechanistic questions unanswered. Biophysical Chemist / NMR Spectroscopist: Professor Ann McDermott 23 Our research interests center on the development of selection strategies for identifying enzymes from large pools of proteins. This research is interdisciplinary, bringing together the techniques of small-molecule synthesis, molecular and cellular biology, computer modeling, and mechanistic enzymology and structural biology. The need for efficient catalysts is fundamental. Biological catalysts drive cellular processes, and the chemical industry relies on catalysts for the synthesis of compounds ranging Molecular Biologist / Organic Chemist: from pharmaceuticals to materials. Professor Virginia Cornish 24 The Tools of the Trade 1 H 2 He 3 Be 4 Li 5 C 6 N 7 O 8 B 9 Ne 10 F 11 Mg 12 Na 13 14 18 Al Si 15 P 16 S 17 Cl Ar 19 20 Sc 21 22 24 Mn 25 Fe 26 Co 27 Ni 28 Cu 29 Zn 30 Ga 31 Ge 32 As 33 Se 34 Br 35 Kr 36 K Ca Ti 23 V Cr 37 38 41 Mo 42 Tc 43 Ru 44 Rh 45 Pd 46 Ag 47 Cd 48 49 50 Sb 51 Te 52 53 54 Rb Sr 39 Y 40 Zr Nb In Sn I Xe 55 Ba 56 La 57 Hf 72 Ta 73 74 75 Os 76 77 79 Hg 80 Tl 8l Pb 82 83 84 At 85 Rn 86 Cs W Re Ir 78 Pt Au Bi Po 87 88 Ac 89 104 Fr Ra Rf 105 Ha 106 Sg 107 Bh 108 Hs 109 Mt 58 59 60 Pm 61 Sm 62 Eu 63 Gd 64 Tb 65 Dy 66 Ho 69 Yb 71 67 68 70 Lu Ce Pr Nd Er Tmi 90 Pa 91 92 93 Pu 94 Am 95 Cm 96 Bk 97 Cf 98 Es 99 100 Th U Np Md 102 Lr Fm 101 No 103 Periodic Table of the Elements 25 Interesting Applications The KSC-ALS Breadboard Project • Humans take in oxygen, food and water, and expel carbon dioxide and organic waste. Plants utilize carbon dioxide, produce food, release oxygen, and purify water. Inedible plant material and human waste are degraded by microorganisms to recycle nutrients for plants in a process termed resource recovery. 26 When humans establish permanent bases on the Lunar surface or travel to Space for exploration, they need to develop systems to: • produce food • purify their water supply and • create oxygen from the carbon dioxide they expel. Physico-chemical processes can perform the two latter tasks, but only biological processes can perform all three. 27 • A life support system that would perform these regenerative functions, whether strictly by biological means or by a combination of biological and physical-chemical methods, has been called a Controlled Ecological Life Support System (CELSS). • Biological systems utilize plants and microorganisms to perform these life support tasks in a process termed bioregeneration. 28 A CELSS is a tightly controlled system, using crops to perform life support functions, under the restrictions of minimizing volume, 29 mass, energy, and labor. A career alternative for chemists, a multidisciplinary arena to prove the role of Chemistry as a "central science". 30