Microscale Operational Organic Chemistry A Problem-Solving Approach to the Laboratory Course

by Lehman, John W

• ISBN13: 9780130335180
• ISBN10: 0130335185
• Edition: 1st
• Format: Paperback
• Copyright: 2003-05-20
• Publisher: Pearson

Summary

This practical guide to the core operations in the organic lab gives an excellent selection of clever microscale experiments, enabling users to have an excellent resource that encourages scientific problem-solving.The unique problem-solving approach given in this guide encourages readers to master major lab operations, explaining why they are carried out the way they are. Readers will understand each scientific problem, formulate a meaningful hypothesis, and then solve the problem. Sections on qualitative organic analysis and basic operations such as glassware use, conducting chemical reactions, washing and drying operations, purification operations, measuring, and instrumental analyses round out this handy reference work.The extensive appendices, bibliography, and basic operations sections make this an excellent desktop resource for organic chemists and other lab technicians.

Table of Contents

Preface

Introduction

Mastering the Operations

Learning Basic Operations

The Effect of pH on a Food Preservative

Extraction and Evaporation

Separating the Components of Panacetin

Recrystallization and Melting-Point Measurement

Identifying a Constituent of Panacetin

Heating under Reflux

Simple Distillation, Gas Chromatography

Preparation of Synthetic Banana Oil

Fractional Distillation

Addition, Mixing, Sublimation

Preparation of Camphor

Boiling Point, Refractive Index

Identification of a Petroleum Hydrocarbon

Column Chromatography, UV-VIS Spectrometry

Isolation and Isomerization of Lycopene from Tomato Paste

Steam Distillation, Infrared Spectrometry

Isolation and Identification of the Major Constituent of Clove Oil

Thin-Layer Chromatography, NMR Spectrometry

Vacuum Distillation, Optical Rotation

Optical Activity of a-Pinene

Correlated Laboratory Experiments

Investigation of a Chemical Bond by Infrared Spectrometry

Properties of Common Functional Groups

Thin-Layer Chromatographic Analysis of Drug Components

Separation of an Alkane Clathrate

Isomers and Isomerization Reactions

Structures and Properties of Stereoisomers

Bridgehead Reactivity in an SN1 Solvolysis Reaction

Reaction of Iodoethane with Saccharin, an Ambident Nucleophile

Dehydration of Methylcyclohexanols

Synthesis of 7,7-Dichloronorcarane Using a Phase-Transfer Catalyst

Stereochemistry of the Addition of Bromine to trans-Cinnamic Acid

Hydration of a Difunctional Alkyne

Preparation of Bromotriphenylmethane and the Trityl Free Radical

Chain-Growth Polymerization of Styrene and Methyl Methacrylate

Synthesis of Ethanol by Fermentation

Reaction of Butanols with Hydrobromic Acid

Borohydride Reduction of Vanillin to Vanillyl Alcohol

Synthesis of Triphenylmethanol and the Trityl Carbocation

Identification of a Conjugated Diene from Eucalyptus Oil

Spectral Identification of Monoterpenoids

Synthesis and Spectral Analysis of Aspirin

Preparation of Nonbenzenoid Aromatic Compounds

Mechanism of the Nitration of Arenes by Nitronium Fluoborate

Friedel-Crafts Acylation of Anisole

Structure of a Natural Product in Anise Oil

Identification of an Oxygen-Containing Organic Compound

Wittig Synthesis of 1,4-Diphenyl-1,3-Butadiene

Effect of Reaction Conditions on the Condensation of Furfural with Cyclopentanone

Haloform Oxidation of 4'-Methoxyacetophenone

Electronic Effect of a para-Iodo Substituent

Synthesis and Identification of an Unknown Carboxylic Acid

Preparation of the Insect Repellent N,N-Diethyl-meta-toluamide

Synthesis of 2-Acetylcyclohexanone by the Stork Reaction

Synthesis of Dimedone and Measurement of its Tautomeric Equilibrium Constant

Preparation of Para Red and Related Azo Dyes

Reaction of Phthalimide with Sodium Hypochlorite

Identification of an Unknown Amine

Preparation and Mass Spectrum of 2-Phenylindole

Nucleophilic Strength and Reactivity in SNAr Reactions

Structure of an Unknown d-Hexose

Fatty Acid Content o

Table of Contents provided by Publisher. All Rights Reserved.

Excerpts

To the InstructorThis book is a microscale laboratory textbook based on the third edition ofOperational Organic Chemistry: A Problem-Solving Approach to the Laboratory Course.Every experiment and minilab in the book can be performed by students using the microscale glassware available in a Mayo/Pike-style microscale lab kit with 14/10 standard-taper joints and threaded connectors. Most of the experiments could also be performed successfully with alternative microscale glassware, such as that provided in a Williamson lab kit, but some might need to be scaled down further and the instructor would have to provide additional instructions regarding the use of the glassware.Some organic chemists regard a "microscale" experiment as one involving approximately 0.1 g of the limiting reactant. Dealing with such small quantities can be discouraging to students with standard scale fingers, who end up with a drop or a few grains of product, if any. Therefore, I have adopted a working definition of a microscale experiment as one that can be performed using the glassware available in a typical microscale lab kit, along with appropriate locker supplies as recommended in theInstructor's Manual.In writing this book, I have been guided by my convictions that students (1) perform better in the organic laboratory course if they master the major lab operations early and apply them throughout the course, (2) learn organic chemistry better if they keep their minds engaged by approaching each experiment as a problem-solving exercise, and (3) perform any task better if they are sufficiently motivated.Part I is devoted to experiments designed to teach the basic laboratory operations, where anoperation,as used here, is a process that utilizes one or more basic lab techniques, such as heating, cooling, and vacuum filtration, to accomplish some end, such as the purification of a solid. Once students have mastered the major operations by completing the appropriate experiments in Part I, they should be ready to apply those operations in Part II, which contains a large selection of experiments that are correlated with topics found in most organic chemistry lecture textbooks. This operational approach helps students understand that an organic synthesis, for example, is not a unique phenomenon that can be experienced only by mechanically following a detailed "recipe." Rather, it is the outcome of a logical sequence of interrelated operations adapted to the requirements of the synthesis.In addition to teaching lab skills, the experiments in this book are designed to help students develop the observational and critical thinking skills that are essential prerequisites for a successful career in science and in virtually every other professional field. Each major experiment requires the student to solve a specific scientific problem through the application of sound scientific methodology. Before an experiment, the student must first define the problem based on information provided in a hypothetical Scenario. After a preliminary reading of the experiment, the student should be able to develop a working hypothesis regarding its outcome. During the experiment, the student gathers and evaluates evidence bearing on the problem and, as necessary, reevaluates and revises the hypothesis based on experimental observations and data. Finally, the student tests the hypothesis by obtaining a melting point, a spectrum, a gas chromatogram, or by some other means, and arrives at a conclusion. Because of the level at which most undergraduate organic chemistry courses are taught, the problems must, of necessity, be kept relatively simple and (with a few exceptions) should not be compared to "real" research problems tackled by professional chemists. It is not the intent of this book to make every student a research chemist; most students who take an organic chemistry course have no intention of going into the field. But the