One-pot preparation of methyl 2-diazo-3-oxopropionates comprising an aqueous ‘sulfonyl-azide-free’ (SAFE) diazo transfer step
摘要:
Methyl 2-diazo-3-oxopropionates were obtained by in situ methoxycarbonylation of methyl ketones followed by diazo transfer onto active methylene group of the intermediate beta-oxo esters. At the second stage, 'sulfonyl-azide-free' (SAFE) diazo transfer protocol in aqueous medium was employed.
Oxidative nitroalkylation of β-ketoamides and nitroalkanes, mediated by hypoiodide generated from tert-butyl hydrogen peroxide and a catalytic amount of guanidinium iodide, afforded the corresponding α-nitroalkyl-β-ketoamides in up to 97% yield.
Iron-Catalyzed Acyl Migration of Tertiary α-Azidyl Ketones: Synthetic Approach toward Enamides and Isoquinolones
作者:Tonghao Yang、Xing Fan、Xiaopeng Zhao、Wei Yu
DOI:10.1021/acs.orglett.8b00409
日期:2018.4.6
transformed into enamides by treatment with FeBr2 at elevated temperature in DMF. The reaction proceeds via 1,2-benzoyl migration from α-carbon to the nitrogen atom, accompanied by expulsion of a nitrogen molecule. This protocol is suitable for the synthesis of N-(cyclopent-1-en-1-yl)benzamides, N-(cyclohex-1-en-1-yl)benzamides, and N-benzoyl-α-methyl enamines and provides a convenient approach toward isoquinolones
We present an efficient synthesis of α-azido-β-dicarbonyl compounds from β-dicarbonylcompounds and trimethylsilyl azide, catalyzed by guanidinium hypoiodite. The reaction can be run in air at ambient temperature (up to 40 °C) and is not sensitive to moisture. The substrate scope is broad, including cyclic and linear β-dicarbonylcompounds, and the α-azide products are obtained in 55%–99% yield.
Zirconium‐Salan Catalyzed Enantioselective
<i>α</i>
‐Hydroxylation of
<i>β</i>
‐Keto Esters
作者:Jie Chen、Haiyang Gu、Xueying Zhu、Wonwoo Nam、Bin Wang
DOI:10.1002/adsc.202000290
日期:2020.7.29
C2‐symmetric salan ligands and cumene hydroperoxide as an oxidant, affording synthetically valuable hydroxylation products in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee) under mild reaction conditions. In mechanistic studies, we have shown that (1) a Zr(IV)‐salan complex was generated in situ as the active catalyst responsible for the chiralinduction, (2) the transfer
The present invention relates to the field of malodor counteraction. More particularly, it concerns malodor masking ingredient having an indane moiety (as defined in formula (I)), as well as malodor masking compositions comprising such ingredients.