ライフサイエンスコーパス: Claisen

1 Claisen condensation, the key step in constructing the p

2 Claisen rearrangement transition states are also highly

3 A Claisen-like rearrangement occurs in the case where ally

4 d via two efficient through processes: (1) a Claisen rearrangement followed by a Ru(VIII)-catalyzed o

5 e synthase, an enzyme which catalyzes both a Claisen condensation and thioester hydrolysis reaction.

6 a link to the indole core is introduced by a Claisen rearrangement from the allylated phenol moiety o

7 a Chan-Lam-type allyloxylation followed by a Claisen rearrangement.

8 er-accelerated catalytic carboalumination, a Claisen rearrangement, and a nucleophilic carbonyl addit

9 dentified, purified, and shown to catalyze a Claisen-type condensation between long chain acyl-CoA su

10 ctions generated the fused tricyclic core, a Claisen rearrangement was used to install an otherwise u

11 nclude a Ru-catalyzed [5+2] cycloaddition, a Claisen rearrangement, and a ring expansion to construct

12 beta-Ketonitriles derived from a Claisen condensation of benzoate esters with alkyl- or p

13 This allylic alcohol is then utilized in a Claisen rearrangement under Johnson's conditions to intr

14 ond cleavage and C1---C9 bond formation in a Claisen rearrangement.

15 tudy of competitive substituent effects in a Claisen-Schmidt reaction, interfacial effects have been

16 The key steps involve a Claisen rearrangement to set up a 4-substituted-3-methyl

17 These were the result of a Claisen condensation (or Knoevenagel type of reaction) o

18 ol derivatives inspired the development of a Claisen/Cope/Diels-Alder cascade reaction.

19 [Chemical reaction: see text] A Claisen rearrangement/iodolactamization sequence startin

20 The latter, when heated, undergo a Claisen rearrangement and form gamma,delta-unsaturated a

21 tive conformation to spontaneously undergo a Claisen rearrangement.

22 tituted cyclopentenols was developed using a Claisen-Sakurai reaction.

23 dium-catalyzed vinyl transfer coupled with a Claisen reaction was used to produce the aldehyde requir

24 activation parameters are consistent with a Claisen rearrangement as the rate-limiting step.

25 f a resonance stabilized DcA reaction with a Claisen rearrangement for the synthesis of multisubstitu

26 tion of cyclic carbonate 90 in tandem with a Claisen rearrangement that generates the octenalactone p

27 The carbanion-accelerated Claisen rearrangement has been extended to include phosp

28 phosphorus-stabilized, carbanion-accelerated Claisen rearrangements proceed rapidly at room temperatu

29 d allylic alcohols via nucleophilic addition/Claisen rearrangement/cyclization reaction is described.

30 the strategy is a tandem Claisen/Diels-Alder/Claisen rearrangement of a suitably substituted xanthone

31 An enantioselective alkoxylation/Claisen rearrangement reaction was achieved by a strateg

32 col is described for an asymmetric allenoate Claisen rearrangement.

33 Key steps include the O-allylation/Claisen rearrangement of spirolactone systems, which are

34 earrangement known as a 3-aza-Cope (or amino-Claisen) reaction.

35 In metal-dependent aldol and Claisen reactions, acidic residues often function either

36 lic isomerizations, allylic alkylations, and Claisen rearrangements.

37 esized through Willimison etherification and Claisen-Schmidt condensation.

38 Benzothiazole formation and Claisen rearrangement involve the cleavage of S-S and C-

39 rbase reagent was tested in Knoevenagel- and Claisen-Schmidt-type condensations and showed conversion

40 gies toward the synthesis of morpholines and Claisen rearrangement products based on the divergent re

41 relative positions of the bis-pericyclic and Claisen rearrangement transition states may control peri

42 diastereoselective examples of archetypical Claisen rearrangements.

43 amolecular C-H phenolization via an aromatic Claisen rearrangement of the respective Mitsunobu adduct

44 in particular, Johnson-Claisen and aromatic Claisen.

45 regioselectivity of the associated aromatic Claisen rearrangement.

46 very of the efficient catalysts for aromatic Claisen rearrangement.

47 ent data on the regioselectivity of aromatic Claisen rearrangements with meta-substituted benzenes.

48 atalysts have been designed for the aromatic Claisen rearrangement of a 1,1-dimethylallyl coumarin.

49 to-enol tautomerization step of the aromatic Claisen rearrangement to be the rate-determining step.

50 The aromatic Claisen rearrangements of allyl p-R-phenyl ethers (R = C

51 tion (for ketones and aldehydes), as well as Claisen condensation reactions.

52 lyase homologs that have been known only as "Claisen condensation" enzymes so far.

53 The catalytic asymmetric Claisen rearrangement of a Gosteli-type allyl vinyl ethe

54 ported relying on a key efficient asymmetric Claisen rearrangement, triggered by electrophilic activa

55 Using an aza-Claisen rearrangement as the key step, 7-prenylindole ha

56 ediate and its transformation through an aza-Claisen rearrangement to the desired pyridine product.

57 Although the aromatic aza-Claisen rearrangement is a general strategy for accessin

58 ssentially constitutes a Pd(0)-catalyzed aza-Claisen rearrangement of N-allyl ynamides, which can als

59 -Heterocyclic carbenes (NHCs) catalyzing aza-Claisen rearrangement of alpha,beta-unsaturated enals wi

60 can then undergo a base-catalyzed domino aza-Claisen rearrangement/cyclization reaction sequence, sim

61 Both routes utilized an efficient aza-Claisen rearrangement to establish the absolute stereoch

62 mbination involves addition-elimination, aza-Claisen rearrangement, tosyl migration, and aromatizatio

63 d acid catalyzed enantioselective indole aza-Claisen rearrangement for the synthesis of chiral 3-amin

64 stigations into Pd-catalyzed and thermal aza-Claisen-carbocyclizations of N-allyl ynamides to prepare

65 onyl shift was made when examining these aza-Claisen rearrangements thermally.

66 ity for an alternative intramolecular Bellus-Claisen-type rearrangement rather than an expected intra

67 domain of the molecule involved a biomimetic Claisen/Diels-Alder cascade, whereas the novel spiroxala

68 xybutyronitrile and the respective esters by Claisen condensation and subsequent Paal-Knorr pyrrole s

69 p, allylation of the 5-hydroxyl, followed by Claisen rearrangement under microwave conditions with co

70 ether 23 by Petasis olefination, followed by Claisen rearrangement.

71 Highly enantioselective catalytic Claisen rearrangements of ester-substituted allyl vinyl

72 roplets is demonstrated for a base-catalyzed Claisen-Schmidt condensation, hydrazone formation from p

73 Indeed, upon Cfa7-catalyzed Claisen condensation between enzyme-bound malonate and a

74 The N-heterocyclic carbene (NHC)-catalyzed Claisen rearrangement of hybrid Ireland-Coates structure

75 ts were discovered as superior in catalyzing Claisen rearrangements of allyloxy- or proparyloxy-subst

76 Unlike in the classical Claisen condensation, however, the VAT-Claisen reaction

77 In the competing Claisen rearrangement, a very large 18O isotope effect a

78 roups, by a novel tandem double condensation/Claisen rearrangement, a gold(I)-catalyzed alkyne hydroa

79 cessed in a combinatorial fashion by a cross-Claisen/ alpha-arylation sequence.

80 ve-assisted oxyanionic 6-exo-dig cyclization/Claisen rearrangement reaction.

81 assisted tandem oxyanionic 5-exo cyclization/Claisen rearrangement sequence.

82 hinckdentine A, which features a dearomative Claisen rearrangement, a diastereocontrolled hydrogenati

83 catalyze this process via a decarboxylative Claisen-like condensation reaction.

84 Here, we show that non-decarboxylative Claisen condensation by polyketoacyl-CoA thiolases offer

85 t with OleA catalyzing a non-decarboxylative Claisen condensation reaction in the first step of the o

86 on- and energy-efficient non-decarboxylative Claisen condensation reactions and subsequent beta-reduc

87 itionally biosynthesized via decarboxylative Claisen condensation by 2-pyrone synthase.

88 e reaction, which is the thioester-dependent Claisen condensation reaction.

89 hat these reactions involve rate-determining Claisen rearrangements followed by subsequent reaction c

90 to the carbodiimide followed by a 1,3-diaza-Claisen rearrangement affords [9,5]- and [9,6]-bicyclic

91 Expansion of the scope of the 1,3-diaza-Claisen rearrangement beyond bridged-bicyclic tertiary a

92 diate followed by the zwitterionic 1,3-diaza-Claisen rearrangement was consistently a higher energy p

93 ermediate followed by the cationic 1,3-diaza-Claisen rearrangement.

94 significantly more reactive toward 1,3-diaza-Claisen rearrangements than isoquinuclidene 2.

95 erionic intermediates that undergo 1,3-diaza-Claisen rearrangements to afford highly substituted urea

96 2 decreases the reactivity toward 1,3-diaza-Claisen rearrangements, while the exodiastereomers 3b an

97 cumulenes are more reactive toward 1,3-diaza-Claisen rearrangements.

98 Metal-catalyzed, double Claisen rearrangement of a bis-allyloxyflavone has been

99 other methods for catalytic enantioselective Claisen rearrangements have not provided a satisfactory

100 t was combined with an Ireland ester enolate Claisen rearrangement.

101 the related Ireland-Claisen and Eschenmoser Claisen/Claisen rearrangements were proposed.

102 lytic, enantioselective Meerwein-Eschenmoser Claisen rearrangement has been achieved.

103 col for the dearomative Meerwein-Eschenmoser-Claisen rearrangement of 3-indolyl alcohols that provide

104 y crossover observed between the Eschenmoser-Claisen rearrangement and the thio-Claisen rearrangement

105 de, and diisopropylamine, via an ortho ester-Claisen rearrangement from a propargylic alcohol, or via

106 ain, and the other to prephenate by a facile Claisen rearrangement.

107 c triad and its role in catalyzing the final Claisen-type cyclization to the aflatoxin precursor, nor

108 ne were determined as the rate constants for Claisen-type addition of glycine to 1 where deprotonatio

109 Formal Claisen rearrangement gives alpha-benzoyloxyazo compound

110 A sequential allyl vinyl ether formation-Claisen rearrangement process catalyzed by a palladium(I

111 allylic alkoxides gave products arising from Claisen rearrangement, providing access to keto-alkenes

112 d its recently established synthetic role in Claisen/Dieckmann cyclization and product release.

113 ed tandem Suzuki coupling and intramolecular Claisen-Schmidt condensation pathway.

114 S subsequently catalyzes dual intramolecular Claisen and aldol condensations of this linear intermedi

115 was obtained by a similar strategy involving Claisen rearrangement to transfer an allyl group from th

116 e reaction proceeds via a reductive iodonium Claisen rearrangement of in situ-generated beta-pyridini

117 gent approach featuring (1) a double Ireland Claisen rearrangement to establish key core bonds with c

118 The key step is a tandem Ireland Claisen/Cope rearrangement sequence, wherein the Ireland

119 rearrangement sequence, wherein the Ireland Claisen rearrangement effects ring contraction to a stra

120 dienes via sequential N-alkylation, Ireland-Claisen ester enolate rearrangement and esterification.

121 as synthesized through the use of an Ireland-Claisen [3,3]-sigmatropic rearrangement.

122 A divergent synthesis with an Ireland-Claisen rearrangement as the key step allowed access to

123 um-catalyzed hydroformylation and an Ireland-Claisen rearrangement.

124 roduct was then obtained by using an Ireland-Claisen ring contraction of 37.

125 epi-basiliolide C are achieved by an Ireland-Claisen/Diels-Alder cascade.

126 tudies of the aldol condensation and Ireland-Claisen rearrangement of the resulting Et 3N-solvated en

127 zes on the highly diastereoselective Ireland-Claisen rearrangement of an acyclic alpha-branched allyl

128 A one-pot difluorocyclopropenation/Ireland-Claisen rearrangement sequence applied to readily availa

129 ion, substrate-directed epoxidation, Ireland-Claisen rearrangement, and diastereotopic group selectiv

130 An initial Ireland-Claisen rearrangement produced the benzannulated enyne-a

131 Last, the tandem metathesis/Ireland-Claisen was utilized to access 4-substituted-3,5-cyclohe

132 A novel Ireland-Claisen approach to the putative structure of eupomatilo

133 thetic sequence involving the use of Ireland-Claisen rearrangement of propargylic acetates to form th

134 is based on the early application of Ireland-Claisen rearrangement, macrolactamization, and a late-st

135 ynthetic equivalents for the related Ireland-Claisen and Eschenmoser Claisen/Claisen rearrangements w

136 s to allyl fumarates with subsequent Ireland-Claisen rearrangement has been accomplished yielding sub

137 The tandem, sequential use of the Ireland-Claisen rearrangement also proved suitable for chirality

138 The Ireland-Claisen rearrangement is effectively utilized to establi

139 The Ireland-Claisen rearrangement is the central step in the synthes

140 tal/theoretical investigation of the Ireland-Claisen rearrangement of tetrasubstituted alpha-phthalim

141 The Ireland-Claisen rearrangement of the bis-allylic esters occurred

142 The Ireland-Claisen rearrangement proceeds with high diastereoselect

143 In the case of cyclodienes, the Ireland-Claisen rearrangement produced s-trans locked dienes whi

144 Remote stereocontrol in the Ireland-Claisen rearrangement using a chiral acetonide that serv

145 marked (20-fold) acceleration of the Ireland-Claisen rearrangement with evidence of autocatalysis.

146 sembling commodity materials via the Ireland-Claisen sigmatropic rearrangement.

147 The Ireland-Claisen was conducted across both acyclic and cyclic die

148 This Ireland-Claisen rearrangement delivered approximate 1:1 mixtures

149 ction and chirality transfer through Ireland-Claisen rearrangement as key steps.

150 tive [2,3]-Wittig-oxy-Cope and isomerization-Claisen rearrangements.

151 readily obtained using olefin isomerization-Claisen rearrangement (ICR) reactions to prepare the key

152 iversity available from olefin isomerization-Claisen rearrangement (ICR) reactions.

153 A one-pot isomerization-Claisen protocol has been developed for the synthesis of

154 or ruthenium hydride-mediated isomerization/Claisen rearrangement cascade and a ring-closing metathe

155 logenation of a simple alkene, and a Johnson-Claisen rearrangement that generates a quaternary carbon

156 symmetric alkylation, and asymmetric Johnson-Claisen rearrangement to set six of the seven chiral cen

157 (97% ee), followed by an orthoester Johnson-Claisen [3,3]-sigmatropic rearrangement to construct a s

158 Orthoester Johnson-Claisen rearrangement of allyl alcohol (+)-9 (98% ee) in

159 ropic rearrangements, in particular, Johnson-Claisen and aromatic Claisen.

160 A novel benzyl fluoride Michael-Claisen reaction sequence was developed to construct the

161 repared by a convergent, single-step Michael-Claisen condensation of AB precursor 1 or 2 with D-ring

162 ations include a diastereoselective modified Claisen condensation, a chemo- and diastereoselective re

163 conjugation proceeds by a nondecarboxylative Claisen condensation.

164 ts into the competition between the observed Claisen-type reaction and the historically expected (2 +

165 mical outcome is defined by a combination of Claisen stereospecificity and stereoelectronic effects i

166 hat the rate of coupling exceeds the rate of Claisen condensation.

167 surfactants were used to study the scope of Claisen-Schmidt reactants, and a wide scope on both arom

168 ong the reaction coordinate for this type of Claisen enzyme.

169 thways followed by either tautomerization or Claisen rearrangement.

170 urs rather than the stepwise Michael-type or Claisen-type pathways.

171 etone 16 has been prepared by using an oxaza-Claisen rearrangement, followed by nitrogen deprotection

172 st energy pathway (cation-accelerated oxonia Claisen rearrangement) originates from the second most s

173 quent reactions leading to anomalous phospha-Claisen products were found.

174 These subsequently undergo phospha-Claisen type rearrangement reactions to give the respect

175 zyloxy group and, apparently, follow a photo-Claisen-type mechanism.

176 ), in combination with photo-Fries and photo-Claisen-type reactions of 1-naphthyl (R)-2-phenylpropano

177 The regio- and stereochemistries of photo-Claisen reactions of 1-naphthyl (R)-1-phenylethyl ether

178 In hexane at 23 degrees C, the photo-Claisen products from irradiations of (R)-2 retain up to

179 The primary Claisen products can be elaborated to various derivative

180 ic acid residue (Glu117beta) likely promotes Claisen condensation by acting as the catalytic base.

181 The tandem gold(I)-catalyzed propargyl Claisen rearrangement/hydroarylation reaction of suitabl

182 cess entailing the Au(I)-catalyzed propargyl Claisen rearrangement/Nazarov cyclization of propargyl v

183 cess entailing a gold(I)-catalyzed propargyl Claisen rearrangement/Nazarov cyclization, a [4+2] cyclo

184 The propargyl Claisen rearrangement is a known protocol to gain access

185 t to catalyze the first elongation reaction (Claisen condensation) of type II fatty acid synthesis in

186 anic reactions, namely Diels-Alder reaction, Claisen rearrangement, and Cope-type hydroamination.

187 is stereochemically complementary to related Claisen rearrangement reactions--processes that typicall

188 sms by which the free energy of a repetitive Claisen-like reaction is harnessed to guide the growing

189 l transition state, as well as a [3,3]-retro-Claisen rearrangement to recycle the IMDA product into l

190 analogue, the product leporin C, and a retro-Claisen reaction transition-state analogue to understand

191 ngle ambimodal transition state, and a retro-Claisen rearrangement.

192 le Michael addition and aromatization (retro-Claisen cleavage and amine elimination).

193 ic end product via the (SAM-dependent) retro-Claisen rearrangement catalysed by LepI.

194 he product of the asymmetric enzymatic retro-Claisen reaction [(S)-3-oxocyclohexyl]acetic acid.

195 les with allylic alcohols using facile retro-Claisen cleavage to form reactive intermediates in situ.

196 led a cascade Michael-hemiketalization-retro-Claisen reaction resulting in the C-C(CO) bond cleavage

197 A nucleophilic retro-Claisen ring-opening of donor-acceptor cyclobutenes, for

198 -catalyzed tandem Diels-Alder reaction/retro-Claisen rearrangement.

199 ketone pronucleophile, undergo in situ retro-Claisen activation to generate an allylic acetate and a

200 eeds initially and is followed by the A-ring Claisen reaction.

201 his reaction cascade suggest that the C-ring Claisen/Diels-Alder rearrangement proceeds initially and

202 doxal-glycine iminium ion to form the second Claisen-type adduct 3 as the major reaction product.

203 C) hybrids were synthesized via a sequential Claisen-Schmidt-Knoevenagel-Heck approach and evaluated

204 )-catalyzed olefin isomerization and in situ Claisen rearrangement to afford stereodefined beta-boryl

205 th the carbonyl carbon of 1 to form a stable Claisen-type adduct.

206 approach is convergent and uses a late-stage Claisen-like enolate/acid chloride coupling to establish

207 ction with styryl bromide via O-styrylation, Claisen rearrangement, ene reaction, and O-alkylation oc

208 yl group to a carboxylic acid and subsequent Claisen condensation with acetyl-CoA.

209 onate 46, methylenation of 46 and subsequent Claisen rearrangement of the corresponding alkenyl-subst

210 duce a highly congested ketone, and a tandem Claisen-ene cascade that establishes the 8-membered ring

211 Central to the strategy is a tandem Claisen/Diels-Alder/Claisen rearrangement of a suitably

212 c ketone 33 was prepared by sequential Tebbe-Claisen rearrangement of lactones 29 and 30, which origi

213 The Claisen reaction products are elaborated to the chiral S

214 The Claisen rearrangement of aromatic allyl phenyl ether to

215 The Claisen rearrangements of chorismate (CHOR) in water and

216 The Claisen self-condensation of lactones can be carried out

217 urface by shifting the cycloaddition and the Claisen rearrangement transition states in opposite dire

218 r Diels-Alder reaction, and the Cope and the Claisen rearrangements) have been characterized.

219 ts alkylation of indole with benzhydrol, the Claisen-Schmidt condensation of benzaldehyde and hydroxy

220 addition transition state is followed by the Claisen rearrangement transition state.

221 etoacyl ACP synthase I mtKasA, catalyzes the Claisen-type condensation reaction responsible for fatty

222 oA lyase, a well-known enzyme catalyzing the Claisen condensation of acetyl-CoA with glyoxylate and y

223 electrostatic "solutions" to catalyzing the Claisen rearrangement in CMs.

224 ovides a unique mechanism for catalyzing the Claisen rearrangement on the microsecond lifetime of the

225 wo reaction cascades occurring following the Claisen rearrangements of aryl propargyl ethers to the a

226 New insight into solvent effects for the Claisen rearrangement is presented herein, and a QM/MM a

227 in highly enantioselective catalysts for the Claisen rearrangement of allyloxy- and propargyloxy-indo

228 by the chorismate mutase (CM) enzyme for the Claisen rearrangement of chorismate to prephenate has be

229 he transition state, were calculated for the Claisen rearrangement of chorismate to prephenate in six

230 uch like those observed traditionally in the Claisen condensation.

231 irst examples of asymmetric induction in the Claisen rearrangement with chiral, phosphorus, anion-sta

232 of a short-lived ketone intermediate in the Claisen rearrangement, a task that is challenged by a th

233 largely due to synthetic limitations of the Claisen condensation.

234 d, and together they enhance the rate of the Claisen rearrangement by a factor of 58 over the backgro

235 Solvent effects on the rate of the Claisen rearrangement of chorismate to prephenate have b

236 lowed by subsequent reaction cascades of the Claisen rearrangement products depending on the presence

237 eterocyclic carbene catalyzed variant of the Claisen rearrangement.

238 effects on the stereochemical outcome of the Claisen rearrangements have been examined.

239 for information about the association of the Claisen-Schmidt reactants with the micelles and their lo

240 key step of the first approach relies on the Claisen rearrangement of glucal 18 to provide ester 20a.

241 ole-substituted guanidinium ions promote the Claisen rearrangement of O-allyl alpha-ketoesters and in

242 Thin film formats are used to study the Claisen-Schmidt base-catalyzed condensation of 6-hydroxy

243 on of the methyl group of AcCoA prior to the Claisen condensation to give homocitrylCoA.

244 ant allyl ethers were subjected to a thermal Claisen rearrangement to give the corresponding methyl 7

245 ic iridium(I) catalyst followed by a thermal Claisen rearrangement to provide the allylsilanes in exc

246 -gamma-lactone derivatives using the thermal Claisen rearrangement of the corresponding 3-O- and 2-O-

247 anion formation strategy for asymmetric thio-Claisen rearrangement are documented.

248 mary of our most recent study using the thio-Claisen rearrangement for the synthesis of anti-beta-fun

249 chenmoser-Claisen rearrangement and the thio-Claisen rearrangement is proposed.

250 For the thiono-Claisen rearrangement, a notable structure-reactivity re

251 3,3]-sigmatropic rearrangement of the thiono-Claisen variety that is among the fastest sigmatropic re

252 This Claisen rearrangement establishes the feasibility of DyK

253 ylcyclohexa-2,4-dien-1-one, involved in this Claisen rearrangement was captured and characterized by

254 chain extension by two carbon atoms through Claisen condensation with malonyl-acyl carrier protein.

255 F elimination and C-C bond formation through Claisen rearrangement of in situ generated difluorovinyl

256 l-2-propenone (PA-1) was synthesized through Claisen-Schmidt condensation between acetyl pyrene and s

257 strong sensitivity of the strained esters to Claisen condensation (cyclobutatanes), or facile decompo

258 e PKSs (NR-PKSs) has been shown to extend to Claisen cyclase (CLC) chemistry by catalyzing C-C ring c

259 or Suzuki cross-coupling provides a route to Claisen adducts previously inaccessible from the ICR met

260 aldehyde with an o-hydroxyacetophenone under Claisen-Schmidt conditions afforded a chalcone that was

261 ituted beta-diketones were synthesized under Claisen-Schmidt-type condensation conditions.

262 precursor obtained from an "underdeveloped" Claisen rearrangement of an aryl dienyl ether.

263 Specifically, the unimolecular Claisen rearrangement of allyl p-nitrophenyl ether (ApNE

264 been achieved with its heteroatom variants (Claisen, aza-Cope, and so on).

265 sical Claisen condensation, however, the VAT-Claisen reaction described herein is rendered irreversib

266 d enantioselective variants of the venerable Claisen rearrangement remain relatively rare.

267 o the intramolecular delivery of ring E (via Claisen rearrangement, Heck-type cyclization, or radical

268 e-tethered chromanone/coumarin scaffolds via Claisen rearrangement using a solid state melt reaction

269 or 2 is quite rapid at -78 degrees C, while Claisen cyclization of the enolate produced is rate-dete

270 The data are consistent with Claisen condensation from KS to the ACP carrier site bei