A. C. Knipe The New University of Ulster Coleraine, Northern Ireland
lntramolecular Reactions A n o r g a n i c practical project
Several recent reports (1-6) have described the effectiveness of "project-oriented" (4) laboratory courses. These courses have generally been introduced in an attempt to develop initiative and to prepare students more adequately for practical application of their subject at the graduate level. There have, however, heen relatively few detailed reports (3, 4, 7, 8) of "project-oriented" experiments suitable for inclusion in such courses. One such assignment is the subject of this paper. In the second year of a three year honors chemistry course at The New University of Ulster we require students to undertake a variety of organic practical projects which often border on the research interests of staff members. These projects are open ended in the sense that the scheme of work may be modified in a variety of ways, to accommodate the capabilities of the particular student. We aim also to ensure that each student will gain some sense of achievement and our projects generally iucorporate a "line of least resistance" along which the less able experimentalist can be directed. Branches of particular interest to a student can be investigated subsequently if time permits. Reactions depicted below are featured in one such project which has been designed to introduce the concept and the variety of intramolecular reactions (9,10) and their mechanistic elucidation (11).
+
~ 4 - @ ~ 4 ~ 1
,-
WCH2CHs0H
I
xy1ae
The sequence involves reaction between a sulfonyl chloride (I) and 2-aminoethanol (11) to give the N-2-hydroxyethyl sulfonamide (111) which is featured in two reaction schemes to he investigated. It should be noted that in aqueous hydroxide (>1.0 M ) sulfonamides (III) and (VIII) (pKa
