ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Boron Compounds, XXXVIII.  -  Regioselective O-Derivatization of D-Mannitol with the Aid of Ethylboron Protective Groups1,2: 3,4: 5,6-Tris(O-ethylboranediyl)-D-mannitol (3) is obtained in 80-98% yield by five routes involving D-mannitol and ethylboron compounds. 1,2,3,4,5,6-Hexakis(O-diethylboryl)-D-mannitol (1) and 1,2,5,6-tetrakis-(O-diethylboryl)-3,4-(O-ethylboranediyl)-D-mannitol (2) can be isolated as intermediates. The partial deborylation of 3 with methanol and of 2 with acetylacetone yields 3,4-(O-ethylboranediyl)-D-mannitol (4). The O-acylation of 4 gives the boron-containing compounds 5a and 5b and the boron-free 0-acyl-O-mannitol derivatives 6a, 6b and 7 in good yield.
    Notes: Aus D-Mannit und Äthylborverbindungen erhält man auf fünf verschiedenen Wegen isomerenfreien 1,2: 3,4: 5,6-Tris(O-äthylborandiyl)-D-mannit (3) in Ausbeuten von 80-98%. 1,2,3,4,5,6-Hexakis(O-diäthylboryl)-D-mannit (1) und 3,4-(O-Äthylborandiyl)-1,2,5,6-tetrakis- (O-diäthylboryl)-D-mannit (2) lassen sich als Zwischenprodukte Isolieren. Partielle Entborylierungen von 2 mit Acetylaceton oder von 3 mit Methanol liefern den 3,4-(O-Äthylborandiyl)-D-mannit (4). Durch O-Acylierung sind aus 4 die Borverbindungen 5a und 5b sowie die borfreien O-Acylderivate 6a, 6b und 7 gut zugänglich.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1993 (1993), S. 189-200 
    ISSN: 0170-2041
    Keywords: ω-Lactims, boryl derivatives of ; ω-Lactims, condensation of ; Amidines, N-acyl, borylsulfoboration of ; ω-Thiolactims, 9-BBN derivatives of ; ω-Thiolactams ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Diethylborylation and Sulfidation of ω-LactamsSeveral reaction modes of ω-lactams [A (n = 3), B (4), C (5), D (6), E (7), F (11)] with Et3B are observed between 20 and 110°C. The Et2B lactims (1) having various degrees of association [(1a)x; 1b; (1d)2 (X-ray structure); 1e; (1f)4] are formed by elimination of 1 mol of ethane. The condensation products [2b; 2c (X-ray structure)] result by elimination of 1.33 mol of ethane together with the lactim derivatives (3b; 3c). Thermolysis (≥ 125°C) of (1d)2, 1e, and (1f)4 leads to mixtures, in which the compounds 2d, e, f and 3d, e, f, resp., have been identified (NMR, MS). Differences of the thermal behaviour of 1a-f (s-cis/trans conformers, cis/trans lactims, association degree) are discussed. - From 2b, c and Hacac the N-acylamidines (4b, c) are obtained, which react with (9-BBN)2S to yield the monomeric 9-BBN-ω-thiolactims [5b; 5c (X-ray structure)]. The latter react with MeOH to give the ω-thiolactams (6b, c) and 9-MeO-9-BBN, from which the 2:2 MeOH addition compound (7)2 (X-ray structure) is obtained.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...