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Chemische Berichte
Volumn 124, Issue 8, 1991, Pages 1837-1843
Alkylations of (R,R)‐2‐t‐Butyl‐6‐methyl‐1,3‐dioxan‐4‐ones which are not Possible with Lithium Amides may be Achieved with a Schwesinger P4 Base
Author keywords

1,3 Dioxan 4 ones, enolates of; Enolates, naked; EPC synthesis; Phosphazene P4 base; Schwesinger's base; Hydroxycarboxylic acids, alkylation of
Indexed keywords

EID: 0000134291     PISSN: 00092940     EISSN: 10990682     Source Type: Journal    
DOI: 10.1002/cber.19911240822     Document Type: Article
Times cited : (82)
References (37)
  • 1
    • 84985737694 scopus 로고    scopus 로고
    • Part of the projected Ph. D. Thesis of T. Pietzonka, ETH Zürich.
  • 2
    • 84987493155 scopus 로고
    • 1,3-Dioxanone Derivatives from ?-Hydroxy-carboxylic Acids and Pivalaldehyde. Versatile Building Blocks for Syntheses of Enantiomerically Pure Compounds. A Chiral Acetoacetic Acid Derivative Preliminary Communication
    • (2a)
    • (1986) Helvetica Chimica Acta , vol.69 , pp. 1147
    • Seebach, D.1    Zimmermann, J.2
  • 9
    • 0000874067 scopus 로고
    • Mono- and Dialkylation of Derivatives of (1R, 2S)-2-Hydroxycyclopentanecarboxylic Acid and -cyclohexanecarboxylic acidvia bicyclic dioxanones: Selective generation of three contiguous stereogenic centers on a cyclohexane ring
    • (1989) Helvetica Chimica Acta , vol.72 , pp. 690
    • Herradon, B.1    Seebach, D.2
  • 10
    • 84985653638 scopus 로고    scopus 로고
    • Aldol condensation products of the dioxanone 1 (→ 5‐alkylidene derivatives) followed by double bond isomerization (→ 5‐alkyldioxinones) gives Michael acceptors the reactions of which eventually lead to 5‐alkyl dioxanones.
  • 11
    • 84984399310 scopus 로고
    • (E,R,R)-5-Alkyliden-2-tert-butyl-6-methyl-1,3-dioxan-4-one: Herstellung aus (R)-3-Hydroxybuttersäure, Cuprat-Additionen und Hydrolysen zu 3-Hydroxycarbonsäuren mit chiralen sekundären Alkylgruppen in 2-Stellung
    • (7a)
    • (1990) Chemische Berichte , vol.123 , pp. 2413
    • Amberg, W.1    Seebach, D.2
  • 12
    • 0001494559 scopus 로고
    • (2R)-5-Alkyl-2-tert-butyl-6-methyl-4H -1,3-dioxin-4-one als Zwischenprodukte zur Herstellung von α,β,β-trisubstituierten β-Hydroxycarbonsäuren unter Selbstregeneration des stereogenen Zentrums von (R)-3-Hydroxybuttersäure
    • (7b)
    • (1990) Chemische Berichte , vol.123 , pp. 2429
    • Amberg, W.1    Seebach, D.2
  • 13
    • 0001494559 scopus 로고
    • (2R)-5-Alkyl-2-tert-butyl-6-methyl-4H -1,3-dioxin-4-one als Zwischenprodukte zur Herstellung von α,β,β-trisubstituierten β-Hydroxycarbonsäuren unter Selbstregeneration des stereogenen Zentrums von (R)-3-Hydroxybuttersäure
    • (7c)
    • (1990) Chemische Berichte , vol.123 , pp. 2429
    • Amberg, W.1    Seebach, D.2
  • 14
    • 84984277407 scopus 로고
    • Direkte Michael-artige Addition von Si-Gruppen an β-Aryl-α,β-ungesättigte Carbonylverbindungen mit R3SiCl/Bu2Cu(CN)Li2
    • (7c)
    • (1990) Chemische Berichte , vol.123 , pp. 2439
    • Amberg, W.1    Seebach, D.2
  • 17
    • 84985644162 scopus 로고
    • Reaktionen von Dienolaten des (R)-2-tert-Butyl-6-methyl-4H-1,3-dioxin-4-ons mid Aldehyden und Ketonen — ein chirales Acetessigester-d4-Reagens
    • following publication
    • (1991) Chemische Berichte , vol.124 , pp. 1845
    • Seebach, D.1    litz, U.2    Uhlmann, P.3
  • 18
    • 84987486427 scopus 로고
    • Brominations of Cyclic Acetals from ?-Amino Acids and ?- or ?-Hydroxy Acids withN-Bromosucinimide
    • The reagents and products A– C are derived from (R)‐3‐hydroxybutanoic acid (see 1), but the reactivities studied in this paper and in previous investigations are of course also applicable to dioxanones derived from other b̃‐hydroxycarboxylic acids. 3‐Hydroxy pentanoic acid
    • (1987) Helvetica Chimica Acta , vol.70 , pp. 1104
    • Zimmermann, J.1    Seebach, D.2
  • 31
    • 84985639911 scopus 로고    scopus 로고
    • 3I; therefore it cannot be used for methylations of too weakly acidic compounds (see also the following footnote).
  • 32
    • 84985726299 scopus 로고    scopus 로고
    • 11,12, in which the imino nitrogen is more hindered, so that better selectivities, for instance between mono‐ and dialkylation, can be achieved.
  • 33
    • 84985674885 scopus 로고    scopus 로고
    • The generated anions may be regarded as the first really ”naked'' anions, due to the size and extreme charge delocalization of the corresponding cation, the protonated P4 base
  • 34
    • 84985706209 scopus 로고    scopus 로고
    • Stilbene and bromo‐diphenylethanc were identified as typical undesired products from base treatments of benzyl bromide
  • 36
    • 84985712852 scopus 로고    scopus 로고
    • have also observed that the sequence of benzylation/methylation of 1 leads to the trisubstituted dioxanone with the 5‐benzyl and the 5‐methyl group trans to each other: hitherto unpublished results. Institut für Organische Chemie der Technischen Universität Berlin, 1990. We thank M. Sefkow for private communication of his results.
    • Schewerowsky, G.1    Sefkow, M.2
  • 37
    • 84985721997 scopus 로고    scopus 로고
    • 10h; all the material used was prepared by T. Pietzonka and H. Schlemper (University of Freiburg).

* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.