Premium
Arene Hydrides, 10 Michael Additions of Anthracene Hydride. Selective Reduction of the ArCC Moiety by Fragmentation of the Michael Adduct
Author(s) -
Sommer Andreas,
Stamm Helmut
Publication year - 1992
Publication title -
liebigs annalen der chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 0170-2041
DOI - 10.1002/jlac.199219920120
Subject(s) - chemistry , michael reaction , deprotonation , adduct , anthracene , moiety , medicinal chemistry , protonation , ketene , hydride , fragmentation (computing) , photochemistry , stereochemistry , organic chemistry , ion , catalysis , hydrogen , computer science , operating system
Anthracene hydride ( AH − ) in THF undergoes Michael addition onto the acrylic acid derivatives 1 and 2 . Secondary reactions of the first formed anions 3 and 4 of the Michael adducts depend on the absence ( 3 ) or presence ( 4 ) of an aryl group in β position. The non‐benzylic 3 or its protonated or deprotonated form can cyclize via ester condensation to yield the “dibenzo‐bicyclo[3.2.2.]nonanones” 10b , c . Deprotonation of the anion 4 by excess AH − usually leads to fragmentation of the CCAr bond formed in the Michael addition. The overall result is a selective C = C reduction of cinnamonic acid derivatives and analogues: PhR′C = C → PhR′CH CH. This fragmentation is hampered in the Michael addition adduct 4h with dimethyl benzylidenemalonate 2h probably due to the necessity of a pronounced conformational reorganization during the fragmentation step.