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Umsetzungen von Dilithio‐nitroalkanen und ‐allylnitroderivaten mit Carbonylverbindungen
Author(s) -
Lehr Friedrich,
Gonnermann Jutta,
Seebach Dieter
Publication year - 1979
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.19790620722
Subject(s) - chemistry , deprotonation , dilithium , benzaldehyde , nitro , medicinal chemistry , tautomer , butyllithium , organic chemistry , catalysis , ion , alkyl
Reactions of dilithio‐nitroalkanes and dilithio‐allynitroalkanes with carbonyl compounds Primary nitro compounds can by acylated via dilithium derivatives 5 with carbonic‐acid derivatives to give α‐nitro esters 6a – i and with carboxylic‐acid esters and anhydrides to give α‐nitroketones 6j – q . In the reaction of 1‐nitro‐1‐buten with two mol‐equiv. of butyllithium, the dilithium compound 10 is formed by successive Michael ‐addition and nitronate deprotonation. Dilithium derivatives 5 also react with ketones and benzaldehyde (→ 18a – g ); the nitro aldols 25 and 26 are likewise formed by addition of doubly deprotonated allylic nitro compounds. Some of the products have been further transformed by reduction or by Nef ‐reactions to the hydrochloride of the α‐amino‐acid 26 , to 2‐amino‐alcohols 28a and 28b , to α‐hydroxyamino‐acid esters 27a – c , to α‐hydroxyimino esters 35 and 36 , to α‐hydroxyimino ketones 31 and 33 , to the α‐diketone 34 , and to the α‐keto ester 37 .