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Enantioselektive Reaktionen an porphinoiden Nickelkomplexen
Author(s) -
Meier Kurt,
Scheffold Rolf
Publication year - 1981
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19810640526
Subject(s) - chemistry , solvolysis , enantioselective synthesis , medicinal chemistry , alcohol , sulfonate , alkoxy group , hydride , stereochemistry , diimide , alkyl , organic chemistry , hydrolysis , catalysis , hydrogen , sodium , molecule , perylene
Enantioselective Reactions on Porphine Type Nickel Complexes The thermodynamically controlled addition of alcohols to (+)‐(1 R )‐[1‐methyl‐8H‐HDP]nickelperchlorate ( 1 ; e.e. 92%) yields exclusively the corresponding cis ‐1,11‐disubstituted porphinoids. Chemical transformation of functional groups in the alkoxy side‐chain of the chiral addition product followed by acid catalyzed elimination yields the derived alcohols and 1 . By this procedure, the following enantioselective transformations were studied: methylation of meso ‐2,3‐butandiol ( 5 ) to (+)‐(2 R ,3 S )‐3‐methoxy‐2‐butanol ( 8a ; e.e. 87%), diimide reduction of 2‐ethylallyl alcohol ( 9 ) to (+)‐(2 R )‐2‐methyl‐1‐butanol ( 12a ; e.e. 15%), and hydride reduction of 4‐hydroxy‐2‐butanone ( 13 ) to (+)‐(3 S )‐1,3‐butandiol ( 16a ; e.e. 20%). Addition of 2,2‐dimethyl‐1,3‐propandiol ( 17 ) to 4 , followed by esterification of the free hydroxy group with trifluoromethanesulfonic anhydride and solvolysis of the sulfonate 19 yielded a bridged complex with unrearranged alkyl chain for which structure 20 is proposed.