ISSN:
0570-0833
Keywords:
Synthetic methods
;
Dihydrooxazoles
;
Oxazoles
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The oxazoline ring system, first prepared in 1884, has only in the last five years been shown to possess considerable utility in the synthesis of a variety of functionalized organic compounds. By appropriate metalation of the 2-alkyl substituent it is possible to prepare a variety of homologated carboxylic acid derivatives, both chiral and achiral. Various other manipulations of the oxazoline ring lead to aldehydes, ketones, lactones, amino acids, thiiranes, and olefins. Due to the inertness of the oxazoline ring system to various reagents (RMgX, LiAlH4, CrO3, mild acid or alkali) it may be utilized as a protecting group for carboxylic acids during the transformations involving the above reagents. Two major new developments in oxazoline chemistry involve (a) the use of a chiral oxazoline as a reagent for asymmetric synthesis of chiral carboxylic acids, lactones, alcohol, thiiranes, and olefins and (b) a new mode of aromatic substitution in which the aryloxazolines act as nucleophilic or electrophilic reagents. This behavior has led to a variety of polysubstituted benzenes and biphenyls which would be inaccessible by classical routes. A variety of examples illustrating the utility of oxazolines indicated above are presented so that the reader may appreciate the vast potential of this simple ring system in synthesis.
Additional Material:
15 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/anie.197602701
