Die Borierung von Lactamen und Harnstoffen mit einem Amino‐imino‐boran
Contribution to the Chemistry of Boron, 201. ‐ Boration of Lactams and Ureas by an Amino‐Imino‐Borane Pyrrolidon reacts with ( tert ‐butylimino)(2,2,6,6‐tetramethylpiperidino)borane ( 1 ) to give the N ‐borated lactam 2 . Diketopiperazine behaves similarly. It is borated on both of its N atoms to fo...
Published in: | Chemische Berichte |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
1990
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Subjects: | |
Online Access: | http://dx.doi.org/10.1002/cber.19901230307 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fcber.19901230307 https://onlinelibrary.wiley.com/doi/pdf/10.1002/cber.19901230307 |
Summary: | Contribution to the Chemistry of Boron, 201. ‐ Boration of Lactams and Ureas by an Amino‐Imino‐Borane Pyrrolidon reacts with ( tert ‐butylimino)(2,2,6,6‐tetramethylpiperidino)borane ( 1 ) to give the N ‐borated lactam 2 . Diketopiperazine behaves similarly. It is borated on both of its N atoms to form 3 . Urea and 1 give access to the O,N,N ′‐triborated isourea derivative 4 , which contains the structural unit of a ketiminoborane. The diborated carbodiimide 10 is ultimately obtained from 1 and thiourea via the triborated isothiourea derivative 9 . MNDO calculations have been used to estimate the relative thermodynamic stabilities of O/N borotropes of carbonic acid amides and lactams. They demonstrate that the O isomers gain in stability by increasing the size of N substituents. |
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