28187-88-4Relevant academic research and scientific papers
Isomerisation of Vinyl Sulfones for the Stereoselective Synthesis of Vinyl Azides
Collins, Niall,Connon, Robert,Evans, Paul,Sánchez-Sanz, Goar
, p. 6228 - 6235 (2020/10/02)
Reported is the construction, and facile base-mediated conversation of ten differently substituted 3-azido E-vinyl sulfones (γ-azido-α,β-unsaturated sulfones) into their isomeric vinyl azide counterparts. The requisite 3-azido E-vinyl sulfones were prepared from 3-bromo E-vinyl sulfones, which in turn were accessed from allyl sulfones via a bromination-elimination sequence. In relation to this a one-pot azidation-isomerisation sequence was developed which enabled the direct formation of the vinyl azides from the corresponding 3-bromo E-vinyl sulfones. Similarly, a convenient one-pot Horner–Wadsworth–Emmons olefination-isomerisation approach was utilised in order to prepare some of the allylic sulfones used in this study. The vinyl azide forming process typically proceeded with high levels of Z-selectivity, although this was dependent on the vinyl sulfone substitution pattern. Thus, with either no substituent or a methyl group in the γ- or β-position, relative to the sulfone, good, to high levels of Z-selectivity (Z/E = 85:15 to ≥ 95:5) were obtained. However, incorporation of an α-sulfonyl methyl substituent led to an E-selective process (Z/E = 20:80). A non-bonding interaction between the azido group and the α-sulfonyl vinylic proton is proposed, which acts as a conformational control mechanism to help guide the stereochemical outcome.
One-Pot Allylation-Intramolecular Vinylogous Michael Addition-Isomerization Cascade of o-Hydroxycinnamates and Congeners: Synthesis of Substituted Benzofuran Derivatives
Harish, Battu,Subbireddy, Manyam,Obulesu, Owk,Suresh, Surisetti
supporting information, (2019/03/19)
A unique intramolecular vinylogous Michael addition leading to the synthesis of heterocycles has been disclosed. Base-promoted one-pot sequential O-allylation of o-hydroxy-cinnamates or -cinnamonitrile or -chalcones with γ-bromocrotonates followed by an intramolecular conjugate addition of vinylogous Michael donors resulted in the formation of highly substituted benzofuran derivatives in good to excellent yields. The intramolecular event followed by two [1,3]-H shifts leading to aromatization appears to be the key to the success of this unprecedented transformation.
Facile synthesis of substituted diaryl sulfones: Via a [3 + 3] benzannulation strategy
Tang, Xiang-Zheng,Tong, Lang,Liang, Hua-Ju,Liang, Jie,Zou, Yong,Zhang, Xue-Jing,Yan, Ming,Chan, Albert S. C.
, p. 3560 - 3563 (2018/05/26)
A base-mediated [3 + 3] benzannulation strategy for the conversion of 1,3-bis(sulfonyl)propenes and β,γ-unsaturated α-ketoesters to diaryl sulfones has been developed. This method provides facile, metal-free and efficient access to highly substituted diaryl sulfones in good to excellent yields. In addition, the sulfonyl group could be easily removed or converted to other functional groups via an organostannane intermediate.
"Syn-Effect" in the Conversion of (E)-Vinylic Sulfones to the Corresponding Allylic Sulfones
Hirata, Takaki,Sasada, Yoshihiro,Ohtani, Takashi,Asada, Takahiro,Kinoshita, Hideki,et al.
, p. 75 - 96 (2007/10/02)
It was found that (E)-vinylic sulfones preferentially afford (Z)-allylic sulfones as kinetically-controlled products by treatment with a base under mild conditions, while (Z)-vinylic sulfones give (E)-allylic sulfones.Such stereochemical relationship was
A SIMPLE METHOD FOR THE SYNTHESIS OF γ-FUNCTIONALIZED VINYL AND ALLYL SULFONES
Najera, Carmen,Perez-Pinar, Alfonso,Sansano, Jose M.
, p. 6337 - 6352 (2007/10/02)
The synthesis of γ-functionalized vinyl sulfones 3 have been carried out directly starting from dibromides 2 derived from allyl sulfones 1 by reaction with different nucleophiles.The process is stereoselective affording compounds 3 with E configuration ex
RING OPENING THREE-CARBON EXTENSION OF 2-CARBOETHOXYCYCLOALKANONES WITH 3-BROMO-1-(p-TOLYLSULFONYL)PROPENE
Masuyama, Yoshiro,Yamada, Kohji,Tanaka, Hiroyuki,Kurusu, Yasuhiko
, p. 1525 - 1532 (2007/10/02)
Reaction with 1,8-diazabicycloundec-7-ene (DBU) of 2--2-carboethoxycycloalkanones, derived from 2-carboethoxy-2-sodiocycloalkanones and 3-bromo-1-(p-tolylsulfonyl)propene, caused ring opening three-carbon extension i
