Document Type
Thesis
Date of Award
6-30-1967
Degree Name
Master of Science in Chemical Engineering - (M.S.)
Department
Chemical Engineering
First Advisor
William H. Snyder
Second Advisor
Howard David Perlmutter
Third Advisor
Gert G. Schlesinger
Abstract
Chemical reactions were carried out to determine the products of the halogenation of cyclic acetals with N-halo compounds (specifically N-bromosuccinimide and N-chlorosuccinimide) under conditions essentially free of those directly associated with free radical mechanisms (photocatalysis, peroxides, azonitriles, etc.).
Cyclic acetals were prepared and halogenated with bromine (Br2) or N-bromosuccinimide (NBS) or N-chlorosuccinimide (NCS). The distilled product from each reaction after workup was analyzed by vapor phase chromatography (VPC). The major components from the VPC were collected and identified by either infrared (IR) or nuclear magnetic resonance (NMR) spectroscopy and elementary analysis.
A mixture of compounds was found in each distilled product with two being predominant and accounting for over 90% of the isolated product makeup. These major compounds are the a-halo alkyl cyclic acetal and the p-halo alkyl ester as per the following general reaction:
(cyclic acetal)(β-halo alkyl ester)(α-halo alkyl cyclic acetal)
Low yields in the order of 15-25 mole percent characterize the reactions with bromine, the workup of which includes a hydrolysis step which may destroy ester and therefore account for the fact that the a-halo alkyl cyclic acetal appears to be the major component in approximately a 6 to 5 ratio to the IB-halo alkyl ester. Yields of 30-50 mole percent were obtained in the reactions with the N-halo compounds, the f3-halo alkyl ester being the major component in approximately a 5 to 1 ratio to the a-halo alkyl cyclic acetal.
The rate and effect of catalysis of these reactions was studied in small scale reactions using trace amounts of water or anhydrous HCl or anhydrous HBr as catalysts. The products from these runs were not analyzed quantitatively but infrared spectroscopy showed them to be similar to those obtained from uncatalyzed reactions.
These reactions are the first to be carried out under conditions relatively free of those directly associated with free radical mechanisms. The results indicate that in general cyclic acetals can be halogenated with N-halo compounds under mild conditions to a product consisting primarily of a halogenated ester and secondly a halogenated cyclic acetal.
Recommended Citation
Hrinkevich, Nicholas, "The reaction of cyclic acetals with N-halo compounds" (1967). Theses. 2625.
https://digitalcommons.njit.edu/theses/2625
