نتایج جستجو برای: sulfones

تعداد نتایج: 1199  

Journal: :Organic & biomolecular chemistry 2011
Adrien Quintard Alexandre Alexakis

The 1,2-sulfone rearrangement resulting from nucleophilic addition to bis activated vinyl-sulfones has been studied in more detail. Various nucleophiles activated by different types of catalysts (enamine, Brönsted base, thiourea) are able to promote such rearrangement in excellent yields and moderate to excellent enantioselectivities (up to 94% ee). Mechanistic studies have led to a better unde...

Journal: :Journal of Polymer Science Part A-1: Polymer Chemistry 1967

Journal: :Nature Communications 2021

Abstract Sulfinyl radicals – one of the fundamental classes S-centered have eluded synthetic application in organic chemistry for over 60 years, despite their potential to assemble valuable sulfoxide compounds. Here we report successful generation and use sulfinyl a dual radical addition/radical coupling with unsaturated hydrocarbons, where readily-accessed sulfones serve as precursor. The stra...

Journal: :Chemical communications 2003
Boyapati M Choudary Chinta Reddy V Reddy Billakanti V Prakash Mannepalli L Kantam B Sreedhar

Osmate-exchanged Mg-Al layered double hydroxides catalysed the delivery of two oxygen atoms simultaneously via a 3 + 1 cycloaddition to sulfide to form sulfone directly for the first time, reminiscent of 3 + 2 cycloaddition in asymmetric dihydroxylation reactions.

Journal: :International journal of Leprosy 1953
R R WOLCOTT H ROSS

Experience with a variety of sulfone and other compounds at Carville since 1941 has shown that the majority of treated patients respond with subjective and objective improvement. The degree of bacteriologic improvement does not keep pace with clinical improvement. The result after years of therapy is often a rather stable leprous process of low-grade activity. In a very small number of cases im...

Journal: :Chemical Society reviews 2012
Jonathan P Brand Jérôme Waser

In addition to the well-established nucleophilic alkynylation, the use of electrophilic alkynes can expand tremendously the scope of acetylene transfer reactions. The use of metal catalysis has recently led to a rebirth of this research area. Halogenoalkynes, hypervalent alkynyliodoniums, acetylene sulfones and in situ oxidized terminal acetylenes are the most often used reagents for electrophi...

2014
Sambasivarao Kotha Rama Gunta

The title compound C15H20O2S, was identified as a product of di-allyl-ation of the meso-isomer of the corresponding norbornene sulfone, and it is an achiral compound. The five-membered heterocycle adopts an envelope conformation with the S atom deviating by 0.795 (3) Å from the other atoms of the ring (r.m.s. deviation = 0.0131). Both allyl groups are anti-oriented relative to the S atom but th...

2017

The cyclo-addition reaction of diazomethane with a,/3-unsaturated sulfones is described. Divinyl sulfone and phenyl vinyl sulfone give 1or 2-pyrazolines depending on the reaction conditions. cisand /rans-l,2-Bis(methylsulfonyl)ethene form pyrazolines, which on reaction with either triethylamine or excess of diazomethane lead to substituted pyrazoles. The addition of diazomethane to doüble bonds...

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