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C. I. Lewis: Susan Haack
No full textLewis, according to Kuklick, was ‘a private person’, of ‘unsparing honesty and … utter dedication to the rational pursuit of truth’. He was, Kuklick continues, ‘equally uncompromising in what he expected of his readers, and as a result wrote for and lectured to a tiny group of scholars’. I hope that—since I occasionally find myself borrowing from him and frequently find myself arguing with him—I may count myself as one of the ‘tiny group of scholars’ for whom Lewis wrote. And perhaps, by arguing with him again here, I may persuade some of you of the enduring interest of his work.</jats:p
Vilsmeier-haack reaction of glycals-a short route to C-2-formyl glycals
No full textA short and straightforward route has been accomplished for the synthesis of C-2-formyl glycals by a Vilsmeier-Haack reaction of glycals
Geologische Karte von Preußen und benachbarten deutschen Ländern / Grad-Abtheilung 41, Blatt 59 [3926] Bockenem
No full textO. Grupe, W. Haack, F. Schucht 1913 ; topogr. Aufnahme des Kgl. Preuß. GeneralstabesKopftitel, Zählung oben links, Maßstäbe unten, Erläuterungen links und rechtsMaßstab in grafischer Form (Meter, Schritt)Mit "Profil A-B", "Profil C-D" und "Böschungs-Maßstab"Mit HöhenangabenNullmeridian: FerroAufgrund der Größe liegt die Karte in 2 Scans vo
Geologische Karte von Preußen und benachbarten deutschen Ländern / Gradabtheilung 55, Blatt 5 [4026] Lamspringe
No full textgeologisch bearbeitet durch O. Grupe, W. Haack und F. Schucht 1906 und 1913Kopftitel, Zählung oben links, Maßstäbe unten, Erläuterungen links und rechtsMaßstab in grafischer Form (Meter, Schritt)Mit "Profil A-B", "Profil C-D" und "Böschungs-Maßstab"Mit HöhenangabenNullmeridian: FerroAufgrund der Größe liegt die Karte in 2 Scans vo
L’usage de la référence étrusque au Ve siècle : L’exemple de Lactantius Placidus et Longinien
No full textHaack Marie-Laurence. L’usage de la référence étrusque au Ve siècle : L’exemple de Lactantius Placidus et Longinien. In: L’Etrusca disciplina au Ve siècle apr. J.-C. La divination dans le monde étrusco-italique, X. Besançon : Institut des Sciences et Techniques de l'Antiquité, 2016. pp. 45-59. (Collection « ISTA », 1356
Vilsmeier-Haack reaction on some 3-buten-2-ols
No full textVilsmeier-Haack reaction of ; ; gave 6-26% benzenes I ; ; ; . The presence of at least 5 appropriate participating C atoms on the butenol backbone was essential for formylative benzocyclization to occur
Use of XtalFluor‑E as an Alternative to POCl<sub>3</sub> in the Vilsmeier–Haack Formylation of <i>C</i>‑2-Glycals
No full textWe report the use of XtalFluor-E
([Et2NSF2]BF4) as an alternative
to POCl3 in the Vilsmeier–Haack
formylation reaction of C-2-glycals. Employing a
XtalFluor-E/DMF combination allowed the desired C-2-formyl glycals to be isolated in 11–90% yield. This method
was extended to the synthesis of a C-2-formylated disaccharide glycal
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Studies toward Total Synthesis of (±)-Caldaphnidine C via One-Pot Sequential Intramolecular Vilsmeier–Haack and Azomethine Ylide 1,3-Dipolar Cycloaddition
No full textAn
application of a one-pot sequential Vilsmeier–Haack cyclization
and intramolecular azomethine ylide 1,3-dipolar cycloaddition toward
the total synthesis of (±)-caldaphnidine C is presented. It allowed
an efficient formation of three cycles with perfect control of four
of the five newly created stereogenic centers including one all-carbon
quaternary center. Two synthetic strategies to produce the key-step
precursor, the investigation and optimization of the cyclization partners
(nucleophile, azomethine ylide, and dipolarophile), and further derivatization
of the cycloadduct are reported
Synthesis of Methylene Bridged Bis-pyrrolo[3,2-c]carbazoles via an Unusual Vilsmeier-Haack Product of N-Ethylcarbazole
No full textThe unexpected result for the formylation of N-ethylcarbazole under the Vilsmeier-Haack conditions (POCl3/DMF) led to the synthesis of novel methylene bridged bis-pyrrolo[3,2-c]carbazoles via Hemetsberger indole synthesis was reported. A plausible mechanism for the formation of unexpectedly synthesized 7,7 '-methylene bis(9-ethyl-9H-carbazole-3-carbaldehyde) 4 was postulated. The full characterization data of dicarbazolylmethane 4 and the bis-pyrrolo carbazoles 10a-b were obtained by utilizing H-1 NMR, C-13 NMR, FT-IR, mass spectrometry and single crystal X-ray diffraction techniques
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