Chemo-enzymatic synthesis of spiro type gem-difluorocyclopropane as core molecule candidate for liquid crystal compounds

Recent advances in the syntheses, transformations and applications of 1,1-dihalocyclopropanes

“…43 Scheme 28 Synthesis of gem-diiodocyclopropane from bismetallated cyclopropane. 43 Scheme 28 Synthesis of gem-diiodocyclopropane from bismetallated cyclopropane.…”

“…The same strategy for generating difluorocarbene has also been used for the difluorocyclopropanation of a dibenzyl ether system to afford a tetrafluoro derivative of 2,8-bis(hydroxymethyl)decane (Scheme 33). 43 Scheme 28 Synthesis of gem-diiodocyclopropane from bismetallated cyclopropane.…”

“…42 Resolution of racemic 1,1,7,7-tetrafluoro-2,8-bis(hydroxymethyl)dispiro[2.2.2.2]decane was achieved using Lipase QL catalyzed enantioselective transesterification (Scheme 72). 43…”

Transition Metal‐free gem‐difluorocyclopropanation of Alkenes with CF3SiMe3−NaI System: a Recipe for Electron‐deficient Substrates

“…Modern medicinal chemistry widely exploits two structural motifs to improve physicochemical characteristics of the compounds: fluorine atoms and small rings . Gem ‐difluorocyclopropanes combine both these structural features and are therefore considered as very promising building blocks for early drug discovery . Among the most prominent examples, experimental antineoplastic drug zosuquidar ( 1 ), which has reached Phase III clinical trials, glutamate analogue 2 – selective mGluR2 (metabotropic glutamate receptor 2) agonist, one more mGluR2 modulator 3 (EC 50 =6.2 nM), Aurora kinase A inhibitor 4 (IC 50 =0.18 nM), nanomolar LPAR2 (lysophosphatidic acid receptor 2) antagonist 5 , or TBK1 (TANK binding kinase 1) inhibitor (IC 50 =0.86 nM) can be mentioned (Figure )…”

New spirocyclic nitroxides of 2,5-dihydroimidazole series flanked by two mesogenic fragments

“…Tschierske and Vögtle et al succeed in the synthesis of a number of calamitic LCs on the basis of mono-and dispiro derivatives of cyclobutanes, cyclopentanes and cyclohexanes. [17][18][19][20][21][22] Interesting results were obtained in the preparation ferroelectric LC`s on the basis of triangular structures (3+3+3) 23,24 and gem-difluoro derivatives of spirocyclopropanes (3+6+3), 25 which showed chiral smectic SmA* and SmC* phases in different conditions. This report is a continuation of the researches on the synthesis of spirocyclic mono-and biradicals of azole series which can show mesogenic properties [26][27][28] and serve as spin probes for diamagnetic LCs by ESR spectroscopy.…”