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Journal of the Korean Chemical Society (JKCS)

ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 7, Number 4
JKCSEZ 7(4)
August 20, 1963 

 
Title
The Synthesis of 2-Methyl-5,5'-gem-Disubstituted-△2-Thiazolines

2-Methyl-5,5'-gem-Disubstituted-△2-Thiazoline계 화합물의 합성
Author
Chi Sun Hahn

한치선
Keywords
Abstract
2-Methyl-5,5'-gem-disubstituted-△2-thiazoline계 화합물의 합성을 1,1'-gem-dusubstituted thiiranesㅓ의 삼원환을 ammonis로 개환하여 해당하는 N-또는 S-acetyl-amino mercaptan을 얻고 그것을 얻고 그것을 다시 폐환하는 방법과 또 하나는 같은 삼원환인 gem-disubstitutes imines을 thiolacetic acid 로 개환하고 그것을 직접 다시 폐환하여 얻은 두가지 방법에 의하여 연구하엿다. 전자는 thiirane ring은 gem-disubtitutionㅓ의 compression 효과에 의하여 극히 안정화되어 여러가지 강력한 반응조건하에서의 sodium amide를 이용한 amide를 사용한 ammonia nuclephile에 책강한 저항을 나타냈으며 반대로 후자의 삼원환 imine은 같은 gem-disubstitution 효과를 받음에도 불순하고 용이하게 개환하였다. 이 gem-disubstitution 효과에 의한 환상화합물의 개환조지성과 폐환촉진성을 입체화학적인 견지에서 고찰하였으며 본연구로서 환상화합물의 안정성에 미치는 gem-disubstitution의 compression 효과는 소위 Thorpe-Ingold bond angle deformation에 연유하는 것이 아니고 오히려 gem-dusubstituents와 이절환상화물내의 hetero atom(s)이 미치는 bond interaction에 기인하다는 결론을 얻었다.

The synthesis of 2-methyl-5,5'-gem-disubstituted-△2-thiazolines has been undertaken by two methods. The first involves the preparation of gem-disubstituted N-or S-acetylamino mercaptan intermediates by ring opening of the corresponding thiiranes with ammonia. The second consists of the ring opening of gem-disubstituted ethylene imines using thiolacetic acid. The thiirane rings have never been opened under conditions as vigorous as that of using sodium amide in liquid ammonia. This is probably due to retardation by the gem-disubstituents. In contrast to this, the corresponding ethylene imine ring opens easily, in spite of the same stereochemical situation. The stabilization of gem-disubstituted cyclic compounds has been discussed from a stereochemical point of view. It has been concluded from the results of this work that the compression effect of gem-disubstitution is not due to bond angle deformation, which was observed by Thorpe and Ingold, but mostly to an electronic bond interaction of the gem-disubstituents and to the hetero atom(s), if any.

Page
230 - 237
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