The reaction of a ketone and an aldehyde in aqueous Na[subscript 2]CO[subscript 2] is described. This experiment is performed in the absence of strong bases or organic solvents and offers the opportunity for students to observe the critical role that reaction temperature and base strength have in determining the product of the base-mediated…

The three-step synthesis of Geodken's macrocycle, H[subscript 2]C[subscript 22]H[subscript 22]N[subscript 4], (5,14-dihydro-6,8,15,17-tetramethyldibenzo[b,i]-[1,4,8,11] tetraazacyclotetradecahexane), in an overall yield of 65% is described. By utilizing the synthesis of the macrocycle's dichloride salt, H[subscript 2]C[subscript 22]H[subscript…

Treatment of d-fructose with methanol in the presence of acid as a catalyst gives a mixture of methyl-[beta]-d-fructopyranoside, methyl-[alpha]-D-fructofuranoside, and methyl-[beta]-d-fructofuranoside, which were separated on an ion exchange column and characterized polarimetrically.

In this interview Roald Hoffmann reveals aspects of his private life, from the great difficulties he experienced during World War II, to his personal beliefs. Hoffmann addresses questions about the meaning of laboratory work, teaching chemistry, representing chemical ideas, his philosophical quandaries, his poetry, and his view of atomic orbitals.…

Competition experiments are a useful tool for preliminary study of the linear free energy relationship of organic reactions. This article describes a physical organic experiment for upper-level undergraduates to identify the rate-determining step of the Claisen-Schmidt condensation of benzaldehyde and acetophenone by studying the linear free…

A simple, novel and generally applicable method to demonstrate structure-activity associations of a group of biologically interesting compounds in relation to receptor binding is described. This method is useful for undergraduates and graduate students in medicinal chemistry and computer modeling programs.

The publicly available free computer program, "SimChemistry," was used as an active learning tool in the chemical engineering curriculum at the University College of Boras, Sweden. The activity involved students writing their own simulation programs on topics in the area of molecular structure and interactions. Evaluation of the learning…

Very often, some type of writing assignment is required in college entry-level Human Anatomy and Physiology courses. This assignment can be anything from an essay to a research paper on the literature, focusing on a faculty-approved topic of interest to the student. As educators who teach Human Anatomy and Physiology at an urban community college,…

Nuclear magnetic resonance (NMR) spectroscopy is widely used by chemists. Furthermore, the use of NMR spectroscopy to solve structures of macromolecules or to examine protein-ligand interactions is popular. Yet, few students entering graduate education in biological sciences have been introduced to this method or its utility. Over the last six…

The prototype of a guided practice application was developed to instruct year 13 biology students in the process of DNA replication. The application uses a high degree of interaction to engage the student in a guided exploration and problem solving exercise. An evaluation revealed that the students showed considerable enthusiasm and significant…

Particle production and solids processing are essential components of the contemporary process industries. Crystalline solids represent a large and important segment of this manufacturing sector. Chemical engineers, especially in the United States, have historically abandoned this subject, leaving it to pharmacists, physical chemists, material…

Outlines the prospects of generating coherent x rays using high-power lasers and indentifies problem areas in their development. Indicates possible applications for coherent x rays in the fields of chemistry, biology, and crystallography. (GS)

The nature of bonding in magnesocene is currently in dispute. This paper presents a brief review of the structure and bonding proposed for magnesocene, leading up to the most recent work. (Author/MA)

Previous articles have dealt with the special problems arising when attempting to reduce reducible representations in continuous point groups. Current work, involving the programing of "projection operators" in connection with numerical computations, also shows the continuous groups to present special problems. These problems are…