Premium
Reactions of Levulinic Acid with Norbornane/ene Amino Acids and Diamines
Author(s) -
Stájer Géza,
Szabó Angela E.,
Csámpai Antal,
Sohár Pál
Publication year - 2004
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.200300604
Subject(s) - chemistry , norbornane , moiety , stereochemistry , ene reaction , heptane , nuclear magnetic resonance spectroscopy , bicyclic molecule , carboxylic acid , methylene , derivative (finance) , pyridine , organic chemistry , financial economics , economics
Whereas the cyclizations of di‐ endo ‐3‐aminobicyclo[2.2.1]heptane‐2‐carboxylic acid ( 2 ) and di‐ endo ‐3‐aminobicyclo[2.2.1]hept‐5‐ene‐2‐carboxylic acid ( 3 ) with 4‐oxopentanoic acid ( 1 ) yield methanodioxopyrrolo[1,2‐ a ][3,1]benzoxazines 6 and 7 , the di‐ exo analogues give either the pyrrolo[1,2‐ a ]pyridine 8 as sole product (in the case of 4 ), or 10 together with the methyl‐substituted derivative 9 (in the case of 5 ). Compound 1 reacts with di‐ exo ‐3‐aminobicyclo[2.2.1]heptane‐2‐methanamine ( 11 ) and di‐ exo ‐3‐aminobicyclo[2.2.1]hept‐5‐ene‐2‐methanamine ( 12 ) to give the methylene‐bridged pyrrolo[2,1‐ b ]quinazolinones 13 and 14 respectively; a pentacyclic product containing a dipyrrolodiazepine moiety 15 was also isolated. The structures and stereochemistry were elucidated by means of IR and NMR spectroscopy, including COSY, DIFFNOE, DEPT, HMQC and HMBC techniques.