109787-11-3Relevant articles and documents
Selective Late-Stage Sulfonyl Chloride Formation from Sulfonamides Enabled by Pyry-BF4
Gómez-Palomino, Alejandro,Cornella, Josep
, p. 18235 - 18239 (2019)
Reported here is a simple and practical functionalization of primary sulfonamides, by means of a pyrylium salt (Pyry-BF4), with nucleophiles. This simple reagent activates the poorly nucleophilic NH2 group in a sulfonamide, enabling the formation of one of the best electrophiles in organic synthesis: a sulfonyl chloride. Because of the variety of primary sulfonamides in pharmaceutical contexts, special attention has been focused on the direct conversion of densely functionalized primary sulfonamides by a late-stage formation of the corresponding sulfonyl chloride. A variety of nucleophiles could be engaged in this transformation, thus permitting the synthesis of complex sulfonamides, sulfonates, sulfides, sulfonyl fluorides, and sulfonic acids. The mild reaction conditions and the high selectivity of Pyry-BF4 towards NH2 groups permit the formation of sulfonyl chlorides in a late-stage fashion, tolerating a preponderance of sensitive functionalities.
Catalytic and autocatalytic mechanisms of acid amplifiers for use in EUV photoresists
Kruger, Seth A.,Higgins, Craig,Cardineau, Brian,Younkin, Todd R.,Brainard, Robert L.
scheme or table, p. 5609 - 5616 (2011/12/15)
Twelve fluorinated acid amplifiers (AAs) were synthesized and studied for use in photoresists exposed to 13.5 nm, extreme ultraviolet (EUV) light. Acid amplifiers are compounds that decompose in the presence of acid to generate more acid via catalytic or autocatalytic mechanisms. These AAs are composed of a body, trigger, and an acid precursor. Thermal decomposition rates of solutions of the AAs in C6D6/m-ethylphenol (50/50 wt %) at 100 °C were monitored by 19F NMR with and without 1.2 equiv. of 2,4,6-tri-t-butylpyridine. All of the AAs in the presence of base decompose according to first-order kinetics with rate constants kBase. The rate constants, kBase, at various temperatures yielded the activation parameters ΔH?, ΔS?, and ΔG?. The enthalpy of activation, ΔH, ?, was in a narrow range of 16.6-19.1 (kcal/mol), whereas the entropy of activation, ΔS?, spanned from 0 to -12 (cal/(mol K)). When acid is allowed to build up in solution (in the absence of base), six of the AAs with tertiary triggers (Body-3) decompose autocatalytically, but the six with secondary triggers (Body-2) are unaffected. Although Body-2 AAs do not decompose autocatalytically, nonaflate acid does catalyze their decomposition. Lithographic evaluation showed that some AAs are capable of simultaneously improving the resolution, line-edge-roughness, and sensitivity of a control EUV photoresist. This simultaneous improvement was quantified using the Z-Parameter. The AAs investigated here were found to improve the Z-Parameter by as much as a factor of 3.
Direct synthesis of thioethers from sulfonyl chlorides and activated alcohols
Martin, Michael T,Thomas, Alford M,York, Douglas G
, p. 2145 - 2147 (2007/10/03)
An efficient, safe one-pot synthesis of thioethers from aromatic sulfonyl chlorides and activated alcohols has been developed under non-aqueous conditions.