ライフサイエンスコーパス: acid catalyst

1 compound functions as an asymmetric Bronsted acid catalyst.

2 the boronate oxygen by the chiral phosphoric acid catalyst.

3 ermediate are presented to the conserved Lys acid catalyst.

4 pyrroline in the presence of a mild Bronsted acid catalyst.

5 steric control upon the addition of a Lewis acid catalyst.

6 with the 2'OH of G8, the implicated general acid catalyst.

7 of a catalytic amount of a chiral phosphoric acid catalyst.

8 was demonstrated using this chiral Bronsted acid catalyst.

9 idize alcohols to carbonyl compounds without acid catalyst.

10 choice of auxiliary and the choice of Lewis acid catalyst.

11 pathways is controlled by the nature of the acid catalyst.

12 [Cu((S,S)-t-Bu-box)](SbF6)2 (1a) as a Lewis acid catalyst.

13 s intermediate presumably requires a general acid catalyst.

14 s is highly dependent upon the nature of the acid catalyst.

15 ified DNAs to implicate Lys-167 as a general acid catalyst.

16 ained by using an acid-exchange resin as the acid catalyst.

17 the vicinity that can function as a general acid catalyst.

18 a) 6.8) should require no assistance from an acid catalyst.

19 nd R to probe its possible role as a general acid catalyst.

20 role of this active-site serine as a general acid catalyst.

21 ng in the presence of a hydride donor and an acid catalyst.

22 rated in the presence and absence of a Lewis acid catalyst.

23 is controlled by use of a chiral phosphoric acid catalyst.

24 g Au(III)-H and water is shown to require an acid catalyst.

25 vnikov hydrothiolation by a dithiophosphoric acid catalyst.

26 ithout the need of a precious metal or Lewis acid catalyst.

27 conditions catalyzed by a Bronsted or Lewis acid catalyst.

28 enables HSbOI to serve as an excellent solid acid catalyst.

29 ing upon the concentration of trimers and an acid catalyst.

30 le as both a VDF delivery vessel and a Lewis acid catalyst.

31 solvents or with hexamethyldisiloxane and an acid catalyst.

32 Coking leads to the deactivation of solid acid catalyst.

33 a over an inexpensive titanium dioxide solid acid catalyst.

34 n is endo-selective in the presence of Lewis acid catalyst.

35 with benzaldehyde in the presence of a Lewis acid catalyst.

36 lizing a nitrated confined imidodiphosphoric acid catalyst.

37 ished through the use of a chiral phosphoric acid catalyst.

38 ed using a chiral confined imidodiphosphoric acid catalyst.

39 eds without involving the Bronsted and Lewis acid catalyst.

40 d phosphoric acid (VAPOL-PA) as the Bronsted acid catalyst.

41 (4+):acac enol-type complex can act as Lewis acid catalyst.

42 umarins in the presence of a chiral Bronsted acid catalyst.

43 y overestimates the computed KIEs for strong acid catalysts.

44 modified dienophile segments; and different acid catalysts.

45 l properties in the rational design of solid-acid catalysts.

46 fined imino-imidodiphosphate (iIDP) Bronsted acid catalysts.

47 he design of improved zeolite-based Bronsted acid catalysts.

48 h various solvents, and with different Lewis acid catalysts.

49 nomeric, macrocyclic, and polymeric sulfonic acid catalysts.

50 nto the Bronsted acidity of a range of solid acid catalysts.

51 acids are the kinetically competent Bronsted acid catalysts.

52 y to aid the design of next-generation Lewis-acid catalysts.

53 ds represent an attractive class of Bronsted acid catalysts.

54 diene 13 in the presence of the chiral Lewis acid catalyst 14 to form 15 (85% yield, 97% ee, >98:2 en

55 iphenylcorrole (TPC) to survey the effect of acid catalyst, acid concentration, ratio of pyrrole to d

56 Solvent, acid catalyst, acid quantity, oxidant, oxidant quantity,

57 A survey of acid catalysts, acid catalyst concentration, DDQ quantit

58 H suggests that Tyr(465) and Tyr(381) act as acid catalysts, activating the epoxide ring and facilita

59 Utilization of protic solvent and Bronsted acid catalyst afforded C-alkylation, whereas, aprotic so

60 kylation, whereas, aprotic solvent and Lewis acid catalyst afforded N-alkylation of 2-oxindoles in go

61 ize the transition state or act as a general acid catalyst after the rate-determining step.

62 lecule to study the acid properties of solid acid catalysts, allowing the identification of distinct

63 NMR data thus indicate that betaPro-1 is the acid catalyst, alphaGlu-52 is a reasonable candidate for

64 Lewis acid catalysts alter the shape of the surface by shiftin

65 With a suitable chiral Bronsted acid catalyst, an oxetane desymmetrization by a well-pos

66 imerizing self-assembly between a phosphoric acid catalyst and a carboxylic acid has recently been es

67 action using ferric chloride both as a Lewis acid catalyst and as an oxidant in excellent yields.

68 AlF(3) plays a dual role as a Lewis acid catalyst and for the building of fluoridized cathod

69 iomab variant of the antibody, may act as an acid catalyst and promote the hydrolysis of acetals.

70 nucleophile using either a Bronsted or Lewis acid catalyst and that the resulting rearrangement proce

71 vent jointly mediated by a chiral phosphoric acid catalyst and the photoredox catalyst Ir(ppy)2(dtbpy

72 n of economic and readily available Bronsted acid catalyst and use of simple starting precursors exem

73 The effects of different amino acid catalysts and substrate substituents on the stereos

74 tionship between the acidities of phosphoric acid catalysts and their reaction activity and selectivi

75 ween anti- and syn-chairs with primary amino acid catalysts and, consequently, the stereoselectivitie

76 acts collectively as a hydride donor, Lewis acid catalyst, and halogen source for the reduction of c

77 er Asp-92 or Asp-72 functions as the general acid catalyst, and that this enzyme undergoes a change i

78 cts simultaneously as a Bronsted base and an acid catalyst, and the mechanism is similar to that of t

79 r the synthesis of benzyne precursors, Lewis acid catalysts, and certain luminophores.

80 es can be altered upon coordination to Lewis acid catalysts, and that these changes can be exploited

81 ility of the solvent and the strength of the acid catalyst are explored.

82 tions demonstrate that both general base and acid catalysts are required for the formation and stabil

83 Functional-group-tolerant Lewis acid catalysts are therefore required to successfully ap

84 Heterogeneous Bronsted acid catalysts are tremendously important in industry, p

85 Chiral acid catalysts are useful for the synthesis of enantioen

86 mically amplified resists (CARs) that employ acid catalysts are widely used throughout the semiconduc

87 ned to probe the respective influence of the acid catalyst, aryl component of AC, nucleophile, and al

88 drate is found to be an efficient and strong acid catalyst as well as an effective protosolvating med

89 an be converted into small hydrocarbons over acid catalysts at high temperatures, we demonstrate an a

90 difficult to understand the surface of solid acid catalysts at the molecular level, despite their imp

91 In the presence of an arylboronic acid catalyst, azole-type heterocycles, including purine

92 The catalysts include four categories: acid catalysts, base catalysts, transition-metal catalys

93 s is presented, covering biocatalysts, Lewis acid catalysts based on boron and metals as well an asso

94 r and alkanol cleavage reactions on Bronsted acid catalysts based on polyoxometalate (POM) clusters a

95 Here, we report using reconfigurable nucleic acid catalyst-based units to build a multipurpose reprog

96 When treated with a stoichiometric Lewis acid catalyst (BF(3)), these diol monoesters form dioxon

97 frameworks (MOFs) are known to act as Lewis acid catalysts, but few reports have explored their abil

98 gLDPE molcat-1 h-1 , surpassing other Lewis acid catalysts by two orders of magnitude.

99 y, and commonly observed reactivity of Lewis acid catalysts cannot be attributed to the eventual form

100 selectivity, outperforming traditional solid acid catalysts (cation-exchange resins, sulfated oxides,

101 to be catalyst dependent; Lewis and Bronsted acid catalysts caused an ionization/SN1' isomerization t

102 A highly reactive and robust chiral Bronsted acid catalyst, chiral N-triflyl thiophosphoramide, was d

103 sights into the structures of imine/Bronsted acid catalyst complexes are presented on the basis of NM

104 A survey of acid catalysts, acid catalyst concentration, DDQ quantity, and reaction

105 in molecules and two to six attached nucleic acid catalysts (deoxyribozymes), with phosphodiesterase

106 -262 was identified as the authentic general acid catalyst, donating a proton to the leaving group ox

107 ites in oxygenated carbon materials in solid acid catalyst-driven chemistry.

108 xyl group of Tyr108 might serve as a general acid catalyst during substrate turnover.

109 Asp38 serves as a general acid catalyst during the 'reverse kinase' reaction by do

110 C could be prepared via a subset of the mild acid catalysts [Dy(OTf)(3) and Yb(OTf)(3)], and a prepar

111 s was investigated to determine whether mild acid catalysts [Dy(OTf)(3), Yb(OTf)(3), Sc(OTf)(3), and

112 to an oligomerization reactor containing an acid catalyst (e.g., H ZSM-5, Amberlyst-70), which coupl

113 and, to some extent, the nature of the Lewis acid catalyst employed.

114 The bifunctional chiral protic acid catalyst enables these reactions to proceed without

115 that a readily accessible chiral carboxylic acid catalyst exerts control over asymmetric cyclization

116 ining a carbonyl organocatalyst with a Lewis acid catalyst facilitates the formation of a carbon-nitr

117 These privileged acid catalysts feature a broad acidity range (pK(a) from

118 s in the presence of Zn(OTf)(2) as the Lewis acid catalyst following an S(N)2-type ring-opening mecha

119 While aspartic acid 135 is the acid catalyst for dehydration in the wild-type enzyme, t

120 Tungstated zirconia is a robust solid acid catalyst for light alkane (C(4)-C(8)) isomerization

121 covalent intermediate by acting as a general acid catalyst for loss of the C4 hydroxyl group.

122 is reported using Ni(ClO4)2.6H2O as a Lewis acid catalyst for nucleophilic amine ring-opening cycliz

123 We show that PtI(4) is an effective Lewis acid catalyst for the activation of terminal alkynes for

124 predicted the most general chiral phosphoric acid catalyst for the addition of nucleophiles to imines

125 riflic acid is also found to be an effective acid catalyst for the direct synthesis of some electron-

126 h a pK(a) of 6.0 and Tyr-74 may be a general acid catalyst for the elimination step, as we found prev

127 uperacid CF3SO3H is found to be an effective acid catalyst for the Knorr cyclization.

128 luated the efficacies of a series of soluble acid catalysts for an intramolecular Friedel-Crafts addi

129 use of metalloenzyme-like zeolites as Lewis acid catalysts for C-C bond formation reactions has rece

130 e a foundation for designing efficient solid acid catalysts for industrial applications.

131 oping new highly porous, heterogeneous Lewis acid catalysts for multicomponent reactions, a new mesop

132 monstrate their utility as reusable Bronsted acid catalysts for the Biginelli synthesis of dihydropyr

133 arboxylate (DMTC) as the most powerful amino acid catalysts for the reaction of both acyclic and cycl

134 ghput catalyst screening and allowed several acid catalysts for the reaction to be identified.

135 echanism in which H61 and H79 act as general acid catalysts for the stereospecific elimination of the

136 red an important supported metal oxide model acid catalyst, for which structure-property relationship

137 ly reactive O-ethyl ketenium ions for use in acid catalyst-free electrophilic aromatic substitutions.

138 tionally, the application of chiral Bronsted acid catalyst furnishes (hetero)aryl C-N atropisomers or

139 hile and Cu(I)-(S)-BINAP as the chiral Lewis acid catalyst, furnishing the desired ring-opening produ

140 n of the anion in the absence of the general acid catalyst, Glu370(H(+)).

141 In the presence of a diarylborinic acid catalyst, glycosyl methanesulfonates engage in regi

142 nes in the presence of Sc(OTf)(3) as a Lewis acid catalyst has been developed.

143 ein, the arene core of ortho-iodoarylboronic acid catalysts has been optimized with regards to the el

144 lysis that their application as strong Lewis acid catalysts has been recognised.

145 kly coordinating anion, like methanesulfonic acid) catalyst has been declared commercially ready.

146 s in understanding the strategies of nucleic acids catalysts has been made by providing thorough stru

147 Lewis acid catalysts have been shown to promote carbonyl-olefi

148 BINOL-derived phosphoric acid catalysts have been used to achieve the synthesis o

149 Cys(45) and Cys(50), the enzyme contains an acid catalyst, His(456), having a pK(a) of 9.2 that prot

150 ated in the aqueous phase with the use of an acid catalyst (hydrochloric acid or an acidic ion-exchan

151 ution and strongly supports A38 as a general acid catalyst in bond scission.

152 ta/alpha)(7)beta-barrel domain serves as the acid catalyst in both reactions.

153 s achieved by the use of a chiral phosphoric acid catalyst in conjunction with diacetyl as a combined

154 thways where aluminum acts either as a Lewis acid catalyst in cooperation with trimethylsilyl halide

155 cyanide in the presence of a palladium Lewis acid catalyst in dichloromethane solvent at room tempera

156 It is shown that CrCl3 is an active Lewis acid catalyst in glucose isomerization to fructose, and

157 ence is the absence of a carboxylate general acid catalyst in RNA triphosphatase.

158 e A plays a major role as an imidazolium ion acid catalyst in the cyclization/cleavage of normal dinu

159 that Tyr-95 does not function as the general acid catalyst in the reaction catalyzed by wild-type PPT

160 the role of both the photo- and chiral Lewis acid catalyst in the reaction sequence.

161 s) have emerged as highly effective Bronsted acid catalysts in an expanding range of asymmetric trans

162 oying up to 10 mol % bulky chiral phosphoric acid catalysts in boiling toluene allowed the product ma

163 ximity (1.2 nm) between photoredox and Lewis acid catalysts in Hf(12)-Ir-OTf, which not only facilita

164 as effective cooperative Bronsted base/Lewis acid catalysts in the asymmetric aldol reaction of isocy

165 nts delivered by bis(oxazoline)-Cu(II) Lewis acid catalysts in the Diels-Alder reaction of cyclopenta

166 the diol on boron and the chiral phosphoric acid catalyst influence the orientation of alpha-vinyl s

167 l diazoacetate in the presence of a Bronsted acid catalyst is described.

168 maldehyde and lactams using recyclable solid acid catalyst is described.

169 sing 1-hydrosilatrane with a chiral Bronsted acid catalyst is reported.

170 For the first time, a Lewis acid catalyst is shown to promote the reaction involving

171 e use of chiral carboxylic acids as Bronsted acid catalysts is much less developed but has recently g

172 tely 10 kcal/mol when phenol, as the general-acid catalyst, is included in the gas-phase calculations

173 conformation, but, functioning as a Bronsted acid catalyst, it also activates the dienophile toward r

174 The flexibility of the hydroxyl carboxylic acid catalyst leads to significant differences in the me

175 dialdehydes with pyrroles in the presence of acid catalysts leads to the formation of a new class of

176 e of d-mannose at the +1 subsite renders the acid catalyst less efficient during the cleavage of the

177 A low Lewis acid catalyst loading (2.5-5.0 mol %) was sufficient to

178 s by a proton juxtaposed at S6 via a general acid catalyst located on the E1 enzyme.

179 on procedures still require aggressive Lewis acid catalysts, multistep procedures to glycosyl donors,

180 The borinic acid catalyst not only influences site-selectivity via a

181 (RD-ROCOP), yet the predominant binary Lewis acid catalyst/nucleophilic cocatalyst systems suffer low

182 elds with a low loading of a bidentate Lewis acid catalyst of 2 to 5 mol %.

183 Fe(OTf)2 was the Lewis acid catalyst of choice for the formation of dihydroquin

184 tes (IDPis) are extremely effective Bronsted acid catalysts of the hetero-Diels-Alder reaction of a w

185 on were observed when polyvalent anthranilic acid catalysts operating on polyvalent aldehyde substrat

186 ful pairing of novel squaramide and Bronsted acid catalysts, our method tolerates a breadth of hetero

187 catalyst (TFA or BF3.OEt2), concentration of acid catalyst, oxidant quantity, and reaction time on th

188 approach was employed, in which a phosphoric acid catalyst, oxidant, and reductant are present in the

189 ructose, and the combined Lewis and Bronsted acid catalysts perform the isomerization and dehydration

190 of Pro-1 functions as the nucleophile and an acid catalyst polarizes the carbon oxygen bond.

191 Highly active palladium-phosphinous acid catalysts POPd, POPd1, and POPd2 have been employed

192 An acid catalyst prepared by partial ion exchange of the hi

193 Herein, we show that chiral acid catalysts promote highly selective visible-light ph

194 Electron-poor arylboronic acid catalysts provide increased reaction efficiency for

195 The chiral Bronsted acid catalyst R-TRIP (3,3'-bis(2,4,6-triisopropylphenyl)

196 When the enantiomeric acid catalyst (R)-A was utilized, the stereoselectivity

197 ards photoexcitation upon binding to a Lewis acid catalyst, rank among the most successful asymmetric

198 e presence of 1 mol % of a chiral phosphoric acid catalyst, reactions reach completion within 10 min

199 th epoxides in the presence of a homogeneous acid catalyst readily delivers the corresponding dioxepi

200 The coordination of a redox-active Lewis acid catalyst reduces the bond-dissociation free energie

201 The counteranion of the acid catalyst remains in the reaction site playing an im

202 0.4 for an essential base and a nonessential acid catalyst, respectively, in the active quaternary Mu

203 ure supports the assignment of Asp405 as the acid catalyst responsible for cleavage of the glycosidic

204 ane with bithiophene diol in the presence of acid catalysts resulted in the formation of unique doubl

205 Depolymerization of PDXL using strong acid catalysts returns monomer in near-quantitative yiel

206 Nucleic-acid catalysts (ribozymes, DNA- and XNAzymes) cleave tar

207 In control: A chiral phosphoric acid catalyst significantly enhances or completely overr

208 ytic performance from a pool of protic/Lewis acid catalysts, signifying its indispensable role as a p

209 dic defect sites on oxide surfaces and Lewis acid catalyst sites consisting of grafted calixarene-Ti(

210 tion state, which is stabilized by the Lewis acid catalyst SnCl(4) and by polar solvents.

211 ide divergent reaction pathways over other n-acid catalysts such as Ag, Pt, Pd, Rh, Cu, In, Sc, Hg, Z

212 Nanoporous acid catalysts such as zeolites form the backbone of cat

213 havior is displayed by strong solid Bronsted acid catalysts, such as H-mordenite and H-beta.

214 (P, olefin) complex and Mg(ClO(4) )(2) Lewis acid catalyst system to promote allylic substitution, pr

215 Using a Rh(I)/DPEphos/benzoic acid catalyst system, terminal alkynes react with sulfon

216 Employing palladium-phosphinous acid catalyst [(t-Bu)(2)P(OH)](2)PdCl(2) allows formatio

217 After survey of pyrrolidine-based Bronsted acid catalyst, tetrazole catalyst (3f) was found to be o

218 t of reactant concentration, reactant ratio, acid catalyst (TFA or BF3.OEt2), concentration of acid c

219 nt, was found to be a highly selective Lewis acid catalyst that affects the heteroacylative dimerizat

220 asymmetric catalysis by a chiral phosphoric acid catalyst that controls both enantioselective additi

221 anism where the 2'OH of G8 acts as a general acid catalyst that is held in position through Watson-Cr

222 encode early vertebrate forms of arachidonic acid catalysts that are widely expressed and are regulat

223 F are reacted with ethylene over solid Lewis acid catalysts that do not contain strong Bronsted acids

224 st that Tyr(381) and/or Tyr(465) are general acid catalysts that facilitate epoxide ring opening in t

225 ectrophiles" function as more powerful Lewis acid catalysts that form upon association of individual

226 on results obtained for homogeneous Bronsted acid catalysts that span a range of pKa values, we sugge

227 Moreover, in the presence of the same acid catalyst, the reactions with beta-2-propenyl substi

228 oncovalent interactions between a phosphoric acid catalyst, the subsequently formed alpha-amino radic

229 r was unaffected by the presence of water or acid catalysts, thereby ruling out reversible Se-O or be

230 ereas the addition of a mixture of the Lewis acid catalysts Ti(O(i)Pr)4 and BF3 enables the formation

231 p-quinone methide using a chiral phosphoric acid catalyst to afford a protected precursor in excelle

232 ymmetric with the use of a chiral phosphoric acid catalyst to afford atropisomeric N-aryl 1,2,4-triaz

233 may serve directly or via water as a general acid catalyst to aid in 5-iminium cation formation.

234 41, which has been considered as the general acid catalyst to assist departure of the leaving nucleob

235 l byproduct, the reaction requires the Lewis acid catalyst to differentiate between the carbonyl of t

236 ssile phosphodiester and serves as a general acid catalyst to expel the OH leaving group of the produ

237 using a polymer-supported chiral phosphoric acid catalyst to introduce asymmetry, followed by select

238 By using a solid acid catalyst to pretreat a gas stream, we have discover

239 prochiral diesters with a chiral phosphoric acid catalyst to produce highly enantioenriched lactones

240 hypothesis that involves the addition of the acid catalyst to the diene, followed by nucleophilic dis

241 id in the precise positioning of the general acid catalyst to the N3 of the imidazole of AICAR.

242 Alcohols can also be activated with boronic acid catalysts to form carbocation intermediates that ca

243 ing the power of these especially mild Lewis acid catalysts to provide novel asymmetric reactions.

244 the proton transfer from Asp164 (the general acid catalyst) to the inhibitor is not.

245 Interestingly, mutation of Asp135, the acid catalyst, to Asn or Ala alters the mechanism, allow

246 The subsequent addition of a Bronsted acid catalyst triggers a cascade process that includes i

247 eds that of the well-known chiral phosphoric acid catalyst TRIP, is largely derived from stabilizatio

248 enantioselectivity of the chiral phosphoric acid catalyst used in these reactions.

249 The efficacy of the new boronic acid catalyst was confirmed by its ability to activate p

250 cid (Asp(60)) invoked as a candidate general acid catalyst was dispensable for phosphohydrolase activ

251 e nitrile substrate by the Bronsted or Lewis acid catalyst was found to be responsible for the rate e

252 Identification of the acid catalyst was performed using an alternative substra

253 propyltrimethoxysilane in the presence of an acid catalyst, water, toluene, and a photoinitiator was

254 acid ketonization reaction over solid Lewis-acid catalysts were examined by nuclear magnetic resonan

255 Chiral Lewis acid catalysts were generated by postsynthesis functiona

256 More specifically, BINAM-derived phosphoric acid catalysts were shown to prevent alkene isomerizatio

257 ies of electrostatically enhanced phosphoric acid catalysts were synthesized and studied.

258 catalyst and His-144 serving as the general acid catalyst, whereas the side chain of Tyr-142 probabl

259 The high acidity of the carboxylic acid catalyst, which exceeds that of the well-known chir

260 was accomplished using a chiral boron-Lewis acid catalyst, which facilitated asymmetric synthesis of

261 tion design is the use of a dithiophosphoric acid catalyst, which gives exclusive alpha-selective add

262 the betaPro-1), implicating betaPro-1 as the acid catalyst, which may protonate C-2 of the substrate.

263 proach leverages a cobalt-based chiral Lewis acid catalyst, which promotes the transformation under t

264 the cage was compared to that of other small acid catalysts, which illustrated large differences in r

265 ular organocatalysts and heterogeneous Lewis acid catalysts, while affording additional recyclability

266 of a naphthyridine using a chiral phosphoric acid catalyst with a Hantzsch ester.

267 n catalysis, most likely acting as a general acid catalyst with a pK(a) value greater than 10.5.

268 ts in a salt bridge with Asp144 as a general acid catalyst with a pK(a) value of 9.7.

269 Meanwhile, isomerization via Lewis acid catalysts with non-nucleophilic counteranions provi