scholarly journals Facile Access to Condensed Arenothiophenes – Preparation of Dihydrophenanthrothiophenes and Dihydrophenanthro[1]Benzothiophenes

2005 ◽  
Vol 2005 (9) ◽  
pp. 564-571 ◽  
Author(s):  
Masataka Watanabe ◽  
Taisuke Matsumoto ◽  
Shuntaro Mataka ◽  
Thies Thiemann
Keyword(s):  
Structural Analysis ◽  
Cross Coupling ◽  
One Pot ◽  
X Ray ◽  
Wittig Olefination ◽  
Crystal Structural

4-Bromo-3-formyl-1,2-dihydronaphthalenes undergo Suzuki cross coupling and Wittig olefination reaction in a one pot procedure. The trienes obtained can be cyclised thermally under concomitant dehydrogenation to dihydrophenanthrothiophenes and dihydrophenanthro[1]benzothiophenes. An X-ray crystal structural analysis was carried out for ethyl (E)-3-[1-(1-benzothiophen-3-yl)-3,4-dihydro-2-naphthyl]propenoate.

Enantioselective Arylation of 3-Carboxamide Oxindoles with Quinone Monoimines and Synthesis of Chiral Spirooxindole-benzofuranones

Synlett ◽  
2019 ◽  
Vol 30 (09) ◽  
pp. 1067-1072
Author(s):  
Hui Chen ◽  
Hui Liu ◽  
Si-Han Zhao ◽  
Shao-Bing Cheng ◽  
Xiao-Ying Xu ◽  
...  
Keyword(s):  
Structural Analysis ◽  
Absolute Configuration ◽  
Tertiary Amine ◽  
The Other ◽  
X Ray ◽  
Quaternary Center ◽  
Crystal Structural ◽  
The Absolute

A highly enantioselective arylation of 3-carboxamide oxoindoles with quinone monoimines is described. Various 3-aryl-3-carboxamide oxindoles with an all-carbon quaternary center were obtained in moderate to good yields (up to 99%) with moderate to good enantioselectivities (up to 98%) in the presence of a bifunctional thiourea-tertiary amine catalyst. The absolute configuration of one product was determined by an X-ray crystal structural analysis and the absolute configurations of the other products can be assigned by analogy. Moreover, several chiral spirooxindole-benzofuranones were synthesized from the 3-aryl-3-carboxamide oxindoles in moderate yields with moderate to good enantioselectivities.

Synthese und Strukturen von Monoalkylamiden und -imiden des Titans / Synthesis and Structures of Monoalkylamides and -imides of Titanium

1991 ◽  
Vol 46 (10) ◽  
pp. 1357-1363 ◽  
Author(s):  
Yüniu Bai ◽  
Mathias Noltemeyer ◽  
Herbert W. Roesky
Keyword(s):  
Structural Analysis ◽  
New Method ◽  
Chlorine Atoms ◽  
Strong Base ◽  
X Ray ◽  
Crystal Structural

A new method for the preparation of monoalkylamides of composition Cp′TiCl2NHR is reported. Me3SnNHR (R = tBu 1a, CHiPr2 1b) reacts with Cp′TiCl3 with elimination of Me3SnCl to yield Cp′TiCl2NHR (2) (2a: Cp′ = C5H5, R = tBu, 2b: Cp′ = Me3SiC5H4, R = tBu, 2c: Cp′ = (Me3Si)2C5H3, R = tBu, 2d: Cp′ = Me4C5H, R = tBu, 2e: Cp′ = Me5C5, R = tBu, 2f: Cp′ = C5H5, R = CHiPr2, 2g: Cp′ = Me3SiC5H4, R = CHiPr2, 2h: Cp′ = (Me3Si)2C5H3, R = CHiPr2, 2i: Cp′ = Me4C5H, R = CHiPr2, 2j: Cp′ = Me5C5, R = CHiPr2). Compounds 2a-2j are stable and eliminate HCl only in the presence of a strong base to form (C5H5TiClNtBu)2 (3a) or (Me3SiC5H4TiClNtBu)2 (3b) from 2a and 2b, respectively. In 3a the chlorine atoms are substituted by NHtBu groups in boiling THF by means of LiNHtBu to give (C5H5TiNHtBuNtBu)2 (4). The reactions of 2e and 2b with LiN(SiMe3)2·Et2O in the presence of pyridine yield Me5C5TiClNtBu · Py (5a) (Py = pyridine) and Me3SiC5H4TiClNtBu·Py (5b), respectively. Compounds 2e and 5a have been characterized by X-ray crystal structural analysis.

Synthesis, Biological Activities, and X-ray Crystal Structural Analysis of 25-Hydroxy-25(or 26)-adamantyl-17-[20(22),23-diynyl]-21-norvitamin D Compounds

2015 ◽  
Vol 58 (24) ◽  
pp. 9510-9521 ◽  
Author(s):  
Yusuke Watarai ◽  
Michiyasu Ishizawa ◽  
Teikichi Ikura ◽  
Flavia C. M. Zacconi ◽  
Shigeyuki Uno ◽  
...  
Keyword(s):  
Structural Analysis ◽  
Biological Activities ◽  
X Ray ◽  
Crystal Structural
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