1007-71-2Relevant articles and documents
Bromomethyl Silicate: A Robust Methylene Transfer Reagent for Radical-Polar Crossover Cyclopropanation of Alkenes
Luo, Wenping,Fang, Yewen,Zhang, Li,Xu, Tianhang,Liu, Yongjun,Li, Yan,Jin, Xiaoping,Bao, Jiakan,Wu, Xiaodong,Zhang, Zongyong
, p. 1778 - 1781 (2020/03/11)
A general protocol for visible-light-induced cyclopropanation of alkenes was developed with bromomethyl silicate as a methylene transfer reagent, offering a robust tool for accessing highly valuable cyclopropanes. In addition to α-aryl or methyl-substituted Michael acceptors and styrene derivatives, the unactivated 1,1-dialkyl ethylenes were also shown to be viable substrates. Apart from realizing the cyclopropanation of terminal alkenes, the methyl transfer reaction has been further demonstrated to be amenable to the internal olefins. The photocatalytic cyclopropanation of 1,3-bis(1-arylethenyl)benzenes was also achieved, giving polycyclopropane derivatives in excellent yields. With late-stage cyclopropanation as the key strategy, the synthetic utility of this transformation was also demonstrated by the total synthesis of LG100268.
MICROBIOCIDAL PICOLINAMIDE DERIVATIVES
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Page/Page column 63, (2019/04/27)
Compounds of the formula (I) wherein the substituents are as defined in claim 1, useful as pesticides, and especially fungicides.
Visible-Light-Promoted Redox-Neutral Cyclopropanation Reactions of α-Substituted Vinylphosphonates and Other Michael Acceptors with Chloromethyl Silicate as Methylene Transfer Reagent
Guo, Ting,Zhang, Li,Liu, Xiaobo,Fang, Yewen,Jin, Xiaoping,Yang, Yi,Li, Yan,Chen, Bin,Ouyang, Minghui
supporting information, p. 4459 - 4463 (2018/09/14)
The alkene cyclopropanation with chloromethyl silicate as a methylene transfer reagent has been accomplished via visible-light-mediated redox-neutral catalysis. This method features broad functional group tolerance and mild conditions. In addition to α-substituted vinylphosphonates, a range of Michael acceptors including α,β-unsaturated acrylate, ketone, amide and sulfone are suitable substrates for this photocatalytic cyclopropanation. An application of this protocol to the cyclopropanation of estrone derivative is also presented. (Figure presented.).
DERIVATIVES OF BENZOTHIAZINES, PREPARATION THEREOF AND APPLICATION THEREOF AS DRUGS
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Page/Page column 117, (2010/09/18)
The object of the present invention is benzothiazine derivatives having the capability of inhibiting 11β-HSD1 not only at an enzymatic level but also at a cell level. The compounds of the present invention are of general formula (I). Wherein notably R1 represents a hydrogen or OR1 represents an ester or an ether. R2 represents a naphthyl or a 1, 2, 3, 4-tetrahydro-naphthalene or a biphenyl or phenyl pyridine or a substituted phenyl. R3 represents a methyl or ethyl; R4 and R'4 represent a hydrogen.
A stereoselective synthetic route to 1,6-dioxaspiro[4.4]non-3-en-2-ones from cyclopropyl alkyl ketones and α-ketoesters
Yang, Yong-Hua,Shi, Min
, p. 1709 - 1712 (2007/10/03)
The SnCl4-mediated reactions of cyclopropyl alkyl ketones with α-ketoesters afford a novel method for the synthesis of 1,6-dioxaspiro[4.4]non-3-en-2-ones with high stereoselectivities in moderate to good yields. This process is a sequential reaction involving a nucleophilic ring-opening reaction of the cyclopropane by H2O, an aldol-type reaction, and a cyclic transesterification mediated by Lewis acid.
Mg-promoted mixed pinacol coupling
Maekawa, Hirofumi,Yamamoto, Yoshimasa,Shimada, Hisashi,Yonemura, Kazuaki,Nishiguchi, Ikuzo
, p. 3869 - 3872 (2007/10/03)
Mg-promoted reduction of a mixture of aromatic ketones (or imines) and aliphatic carbonyl compounds in N,N-dimethylformamide (DMF) brought about unique mixed pinacol type of cross coupling to give unsymmetrical vicinal diols (or amino alcohols) or α-hydroxyketones in good to moderate yields. The reaction may be initiated by electron transfer from magnesium metal to an aromatic carbonyl compound possessing a less negative reduction potential. The difference of reduction potential between aromatic ketones (or imines) and aliphatic carbonyl compounds was found to be one of the important key factors in this selective cross coupling.
NEW VITAMIN D DERIVATIVES WITH CARBO-OR HETEROCYCLIC SUBSTITUENTS AT C-25, A PROCESS FOR THEIR PRODUCTION, INTERMEDIATE PRODUCTS AND THEIR USE FOR PRODUCING MEDICAMENTS
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, (2008/06/13)
The invention concerns new vitamin D derivatives of general formula (I) a process for their production, their use for production of medicaments, and intermediate products used in the process.
Wanderungstendenzen cyclischer, polycyclischer und methylverzweigter Alkylreste bei der Beckmann-Umlagerung
Langhals, Heinz,Ruechardt, Christoph
, p. 3831 - 3854 (2007/10/02)
The migration aptitudes of polycyclic bridgehead groups, cycloalkyl groups as well as of β-, γ- and δ-branched alkyl groups in the Chapman variant of the Beckmann rearrangement were determined.From these data it is concluded that at transition state 2 the migrating group is not resembling a planarised carbenium ion R+, but rather a pentacoordinated carbonium ion structure.Because only small geometrical changes occur in the migrating group vertical stabilisation of charge at transition state is believed to have significant influence on the migration aptitudes.
