Premium
The Use of Polymer Supports in Organic Synthesis. 17. The Synthesis of Unsymmetrical Diamides and Monoamide Monotosylamides from Symmetrical Diamines
Author(s) -
Dixit Dilip M.,
Leznoff Clifford C.
Publication year - 1978
Publication title -
israel journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.908
H-Index - 54
eISSN - 1869-5868
pISSN - 0021-2148
DOI - 10.1002/ijch.197800044
Subject(s) - chemistry , divinylbenzene , tosyl , yield (engineering) , trifluoroacetic acid , cleavage (geology) , styrene , copolymer , polymer , benzene , benzyl alcohol , chloroformate , organic chemistry , polymer chemistry , medicinal chemistry , catalysis , materials science , geotechnical engineering , fracture (geology) , engineering , metallurgy
A 1 or 2% crosslinked divinylbenzene‐styrene copolymer, incorporating benzyl alcohol groups ( 1 ) was treated with p ‐nitrophenyl chloroformate to give a polymer‐bound benzyl p ‐nitrophenyl carbonate ( 2 ). The reaction of ( 2 ) with an excess of the symmetrical diamines 1,4‐diaminobutane ( 3a ), 1,6‐diaminohexane ( 3b ), 1,8‐diaminooctane ( 3c ), 1,10‐diaminodecane ( 3d ) and 1,12‐diaminododecane ( 3e ) gave the respective monoprotected polymer‐bound aminocarbamates ( 4a‐e ). Benzoylation or tosylation of ( 4a‐e ) gave the polymer‐bound N‐benzoyl or N‐tosyl carbamates ( 7a‐e ) or ( 8a‐e ) respectively. Cleavage of ( 7a‐e ) with trifluoroacetic acid liberated the N‐benzoyl‐N'‐trifluoroacetyl‐1, ω‐diaminoalkanes ( 9a‐e ) in 80% yield. Cleavage of ( 8a‐e ) with HCl in benzene, followed by acetylation yielded N‐acetyl‐N'‐tosyl‐1, ω‐diaminoalkanes ( 11a‐e ) in 80% yield. From both cleavage reactions about 20% of the symmetrical diamines were recovered as their N,N'‐ditrifluoroacetyl or N,N'‐diacetyl derivatives ( 10a‐e ) or ( 12a‐e ) respectively.