Competition between Hetero‐Diels‐Alder and Cheletropic Additions of Sulfur Dioxide to 2‐Substituted Buta‐1,3‐dienes. Synthesis of 2‐(1‐Naphthyl)‐ and 2‐(2‐Naphthyl)buta‐1,3‐diene

Chloroprene (=2‐chlorobuta‐1,3‐diene; 4b ) and electron‐rich dienes such as 2‐methoxy‐( 4c ), 2‐acetoxy‐( 4d ), and 2‐(phenylseleno)buta‐1,3‐diene ( 4e ) refused to equilibrate with the corresponding sultines 5 or 6 between −80 and −10° in the presence of excess SO₂ and an acidic promoter. Isoprene ( 4a ) and 2‐(triethylsilyl)‐( 4f ), 2‐phenyl‐( 4g ), and 2‐(2‐naphthyl)buta‐1,3‐diene ( 4i ) underwent the hetero‐Diels‐Alder additions with SO₂ at low temperature. In contrast, 2‐(1‐naphthyl)buta‐1,2‐diene ( 4h ) did not. With dienes 4a, 4g , and 4i , the hetero‐Diels‐Alder additions with SO₂ gave the corresponding 4‐substituted sultine 5 with high regioselectivity. In the case of 4g +SO₂⇄ 5g , the energy barrier for isomerization of 5g to 5‐phenylsultine ( 6g ) was similar to that of the cheletropic addition of 4g to give 3‐phenylsulfolene ( 7g ). The hetero‐Diels‐Alder addition of 4f gave a 1 : 4 mixture of the 4‐(triethylsilyl)sultine ( 5f ) and 5‐(triethylsilyl)sultine ( 6f ). The preparation of the two new dienes 4h and 4i is reported.     

A highly selective synthesis of 1‐substituted (E)‐buta‐1,3‐dienes with 4,4,5,5‐tetramethyl‐2‐vinyl‐1,3,2‐dioxaborolane as building block

Highly selective synthesis of 1‐substituted (E)‐buta‐1,3‐dienes via palladium‐catalyzed Suzuki–Miyaura cross‐coupling of (E)‐alkenyl iodides with 4,4,5,5‐tetramethyl‐2‐vinyl‐1,3,2‐dioxaborolane ( 1 ) is reported. The vinylboronate pinacol ester ( 1 ) acts as a vinyl building block to show high chemoselectivity for the Suzuki–Miyaura pathway versus Heck coupling in the presence of biphasic conditions (Pd(PPh₃)₄, aqueous K₂CO₃, toluene and ethanol). Copyright © 2014 John Wiley & Sons, Ltd.     

Hetero‐Diels‐Alder and Cheletropic Additions of Sulfur Dioxide to 1,2‐Dimethylidenecycloalkanes. Determination of Thermochemical and Kinetics Parameters for Reactions in Solution and Comparison with Estimates From Quantum Calculations

Below −60° and without catalyst, 1,2‐dimethylidenecyclopentane ( 16 ), 1,2‐dimethylidenecyclohexane ( 13 ), 1,2‐dimethylidenecycloheptane ( 17 ), and 1,2‐dimethylidenecyclooctane ( 18 ) add to sulfur dioxide in the hetero‐Diels‐Alder mode, giving the corresponding sultines 4,5,6,7‐tetrahydro‐1H‐cyclopent[d][1,2]oxathiin 3‐oxide ( 19 ), 1,4,5,6,7,8‐hexahydro‐2,3‐benzoxathiin 3‐oxide ( 14 ), 4,5,6,7,8,9‐hexahydro‐1H‐cyclohept[d][1,2]oxathiin 3‐oxide ( 20 ), and 1,4,5,6,7,8,9,10‐octahydrocyclooct[d][1,2]oxathiin 3‐oxide ( 21 ), respectively. Above −40°, the sultines are isomerized into the corresponding sulfolenes 3,4,5,6‐tetrahydro‐1H‐cyclopenta[c]thiophene 2,2‐dioxide ( 22 ), 1,3,4,5,6,7‐hexahydrobenzo[c]thiophene 2,2‐dioxide ( 15 ), 3,4,5,6,7,8‐hexahydro‐1H‐cyclohepta[c]thiophene 2,2‐dioxide ( 23 ), and 1,3,4,5,6,7,8,9‐octahydrocycloocta[c]thiophene 2,2‐dioxide ( 24 ). Kinetics and thermodynamics data were collected for these reactions. The sultines are ca. 10 kcal/mol Diels‐Alder additions (ΔH^≠( 16 −36±3 cal mol⁻¹ K⁻¹) in agreement with third‐order rate laws that imply that two molecules of SO₂ intervene in the transition states of these cycloadditions. Similar observations were made for the cheletropic additions of SO₂. Attempts to simulate the thermodynamics and kinetics parameters of the reactions of SO₂ with dienes 16 and 13 by density‐functional theory (DFT) suggest that the calculations require an appropriate number of polarization functions in the basis set employed. A satisfactory recipe to compute the SO₂ additions to large dienes can be: B3LYP/6‐31G(d) geometry optimizations followed by B3LYP/6‐31+G(2df,p) single‐point calculations or G2(MP2,SVP) estimates on the B3LYP/6‐31G(d) geometries.     

Novel Intramolecular Cyclization of 2‐(Buta‐1,3‐dienyl)benzyl Anions to 6,7(9)‐Dihydro‐5H‐benzocycloheptenyl Anions Leading to Successive Formation of 1,2‐Dihydrocyclopropa[a]naphthalenes

When treated with LiNⁱPr₂ (LDA) at ?78°, 1‐[(methylsulfanyl)methyl]‐2‐[(1Z,3E)‐4‐phenylbuta‐1,3‐dien‐1‐yl]benzene easily cyclized to form benzocycloheptenyl anion, which successively underwent intramolecular nucleophilic substitution to give a cyclopropanaphthalene. Similar LDA‐mediated cyclization also occurred for 4‐phenyl‐ or 4‐methyl‐substituted 1‐[2‐(methoxymethyl)phenyl]buta‐1,3‐dienes to furnish the corresponding benzocycloheptenes and cyclopropanaphthalenes. A 4‐tert‐butyl analog also underwent LDA‐mediated cyclization to give a benzocycloheptene, but not a cyclopropanaphthalene.     

Synthesis of 1,2,3,4‐Tetrahydro‐1,2‐dimethylidenenaphthalene: A Reactive s‐cis‐Butadiene Undergoing Highly Chemo‐ and Regioselective Cyclodimerization

1,2,3,4‐Tetrahydro‐1,2‐dimethylidenenaphthalene 11 has been derived in three steps from tetralone. In the condensed state and at −80°, it undergoes a highly chemo‐ and regioselective cyclodimerization to give 3,3′,4,4′‐tetrahydro‐2‐methylidenespiro[naphthalene‐1(2H),2′(1′H)‐phenanthrene] ( 14 ), the structure of which has been established by single‐crystal X‐ray‐diffraction analysis. Dimer 14 undergoes cycloreversion to diene 11 under flash‐pyrolysis conditions. The reaction of diene 11 with SO₂ occurs without acid promoter at −80° and gives a mixture of (±)‐1,4,5,6‐tetrahydronaphth[1,2‐d][1,2]oxathiin 2‐oxide ( 23 ; a single sultine), 1,3,4,5‐tetrahydronaphtho[1,2‐c]thiophene 2,2‐dioxide ( 25 ), and dimer 14 . The high reactivity of diene 1 in its Diels‐Alder cyclodimerization and its highly regioselective hetero‐Diels‐Alder addition with SO₂ can be interpreted in terms of the formation of relatively stable diradical intermediates or by concerted processes with transition states that can be represented as diradicaloids.     

Palladium‐Catalyzed 2‐Phenylethenylation of Codeine: 8‐[(1E)‐2‐Phenylethenyl]codeinone Dimethyl Ketal as the Unexpected ‘Masked’ Diene for the Preparation of 19‐Substituted Diels–Alder Adducts of Thebaine

In a search for starting materials for the preparation of 7,8‐fused morphine alkaloid derivatives, 8‐[(1E‐2‐phenylethenyl]codeinone dimethyl ketal ( 4 ) and 8‐[(1E‐2‐phenylethenyl]codeine ( 5 ) were prepared. These dienes were used as substrates in the Diels–Alder reactions. Compound 5 formed the ‘normal’ adduct 12 with N‐phenylmaleimide, while compound 4 behaved in reactions with dienophiles as the ‘masked’ diene 11 , a 8‐[(1E)‐2‐phenylethenyl]‐substituted thebaine, yielding the corresponding 19‐substituted 6,14‐endo‐etheno‐6,7,8,14‐tetrahydrothebaines. Specifically, reaction of 4 with methyl vinyl ketone gave rise to 19‐[(1E)‐phenylethenyl]thevinone ( 14 ) whose structure was elucidated by an X‐ray diffraction analysis. The thebaine derivative 11 was also prepared from 4 .     

一种经(E)-α-碘代烯基砜的钯催化交叉偶联反应立体选择合成(1Z,3E)-2-芳砜基取代的1,3-二烯的新方法

（E）-α-Stannylvinyl phenyl（or p-tolyl）sulfones underwent an iododestannylation reaction to afford （E）-α-iodovinyl phenyl（or p-tolyl）sulfones 1, which reacted with （E）-alkenylzirconium（IV） complexes 2 produced in situ by hydrozirconation of terminal alkynes in the presence of a Pd（PPh3）4 catalyst to afford stereoselectively （1Z,3E）-2- phenyl（or p-tolyl）sulfonyl-substituted 1,3-dienes 3 in good yields.     

Gold‐Catalyzed 1,2‐/1,2‐Bis‐acetoxy Migration of 1,4‐Bis‐propargyl Acetates: A Mechanistic Study

The late transition metal catalyzed rearrangement of propargyl acetates offers an interesting platform for the development of synthetically useful transformations. We have recently shown that gold complexes can catalyze a highly selective tandem 1,2‐/1,2‐bis‐acetoxy migration in 1,4‐bis‐propargyl acetates to form 2,3‐bis‐acetoxy‐1,3‐dienes. In this way, (1Z,3Z)‐ or (1Z,3E)‐ and (1E,3Z)‐1,3‐dienes could be obtained in a stereocontrolled manner depending on the electronic and steric features of the ancillary ligand bound to gold and the substituents at the propargylic positions. In this work, we report an experimental study on the scope of this transformation, plus a detailed theoretical examination of the reaction mechanism, which has revealed the key features responsible for the reaction stereoselectivity. Synthetic applications towards the one‐pot synthesis of quinoxaline heterocycles and tandem Diels–Alder processes have also been devised.     

Stereoselective Synthesis of 4,5‐Diethylidene‐Oxazolidinones as New Dienes in Diels‐Alder Reactions

The N‐substituted isomeric (4Z,5Z)‐ and (4E,5Z)‐4,5‐diethylideneoxazolidin‐2‐ones 5 and 6 were synthesized, the latter being favored during the one‐step process from the α‐diketone 1c and different isocyanates. The steric interaction between the N‐substituent and the Me group attached to the exocyclic diene moiety plays a decisive role in controlling the observed stereoselectivity, as suggested by the calculated free energies of the two isomers. Both dienes undergo efficient additions to symmetric dienophiles in thermal Diels‐Alder reactions to yield the adducts 11 and 13 , respectively. These molecules displayed interesting C−H⋅⋅⋅π, and C−H⋅⋅⋅X (X=O, Cl) interactions according to their X‐ray crystal structures. Isomers 6 suffered highly stereo‐ and regioselective additions with nonsymmetrical dienophiles such as methyl vinyl ketone or methyl propiolate. Steric interactions, promoted by the inward‐pointing Me group in 6 , seem to explain such selectivity. These results have also been rationalized by ab initio calculations in terms of the FMO theory.     

Diels–Alder Additions,Ene Reactions,and Condensations of 4‐(Acylamino)‐5‐nitrosopyrimidines – Synthesis of 8‐Substituted Guanines and of 6‐Substituted Pteridinones

4‐(Acylamino)‐5‐nitrosopyrimidines react either by a reductive condensation to provide 8‐substituted guanines, or by a Diels–Alder cycloaddition, or an ene reaction, to provide 6‐substituted pteridinones, depending on the nature of the acyl group and the reaction conditions. Experimental details are provided for the transformation of (acylamino)‐nitrosopyrimidines to 8‐substituted guanines, and the scope of the reaction is further demonstrated by transforming the trifluoro acetamide 25 to the 8‐(trifluoromethyl)guanine ( 27 ), and the N,N′‐bis(nitrosopyrimidinyl)‐dicarboxamide 29 to the (R,R)‐1,2‐di(guan‐8‐yl)ethane‐1,2‐diol ( 32 ). An intramolecular Diels–Alder reaction of the N‐sorbyl (=N‐hexa‐2,4‐dienoyl) nitrosopyrimidine 10 , followed by a spontaneous elimination to cleave the N,O bond of the initial cycloaddition product provided the pteridinones 14 or 15 , characterized by a (Z)‐ or (E)‐3‐hydroxyprop‐1‐enyl group at C(6). Treatment of 10 with Ph₃P led to the C(8)‐penta‐1,3‐dienyl‐guanine 18 . The ene reaction of the N‐crotonyl (=N‐but‐2‐enoyl) nitrosopyrimidine 19 provided the 6‐vinyl‐pteridinone 20a that dimerized readily to 21a , while treatment of 19 with Ph₃P led in high yield to 8‐(prop‐1‐enyl)guanine ( 23 ). The structure of the dimer 21 was established by X‐ray analysis of its bis(N,N‐dimethylformamidine) derivative 21b . The crystal structure of the nitroso amide 10 is characterized by two molecules in the centrosymmetric unit cell. Intermolecular H‐bonds connect the amino group to the amide carbonyl and to N(1). The crystalline bis(purine) 30 forms a left‐handed helix with four molecules per turn and a pitch of 30.2 Å.     

Regioselective Synthesis of Trichloromethyl‐Substituted Salicylates and Cyclohexenones by One‐Pot Cyclizations of 1,3‐Bis(trimethylsilyloxy)buta‐1,3‐dienes

A variety of 6‐(trichloromethyl)salicylates (=2‐hydroxy‐6‐(trichloromethyl)benzoates) were prepared by TiCl₄‐mediated cyclization of 1,3‐bis(trimethylsilyloxy)buta‐1,3‐dienes with 1,1,1‐trichloro‐4,4‐dimethoxybut‐3‐en‐2‐one. The employment of trimethylsilyl trifluoromethanesulfonate (Me₃SiOTf) as Lewis acid resulted in the formation of trichloromethyl‐substituted cyclohexenones. The cyclizations proceeded with good‐to‐very‐good regioselectivities.     

Catalyzed Asymmetric Diels?Alder Reactions of Benzoquinone. Total Synthesis of (−)‐Ibogamine

The Diels? Alder reaction of 1,4‐benzoquinone with 1,3‐dienes catalyzed by Mikami's [Ti{(S)‐binol(2?)}Cl₂] complex (binol=[1,1′‐binaphthalene]‐2,2′‐diol) gives cycloadducts in good yield and in high enantiomer excess. A model is proposed to explain the observed absolute configuration of cycloadducts, and the reaction is used as the key step in an asymmetric synthesis leading to the alkaloid (?)‐ibogamine.     

Reactions of Di(tert‐butyl)diazomethane with Acceptor‐Substituted Ethylenes

Di(tert‐butyl)diazomethane ( 4 ) is a nucleophilic 1,3‐dipole with strong steric hindrance at one terminus. In its reaction with 2,3‐bis(trifluoromethyl)fumaronitrile ((E)‐ BTE ), a highly electrophilic tetra‐acceptor‐substituted ethene, an imino‐substituted cyclopentene 9 is formed as a 1 : 2 product. The open‐chain zwitterion 10 , assumed as intermediate, adds the second molecule of (E)‐ BTE . The ¹⁹F‐ and ¹³C‐NMR spectra allow the structural assignment of two diastereoisomers, 9A and 9B . The zwitterion 10 can also be intercepted by dimethyl 2,3‐dicyanofumarate ( 11 ) and furnishes diastereoisomeric cyclopentenes 12A and 12B ; an X‐ray‐analysis of 12B confirms the ‘mixed’ 1 : 1 : 1 product. Competing is an (E)‐ BTE ‐catalyzed decomposition of 4 to give 2,3,4,4‐tetramethylpent‐1‐ene ( 7 )+N₂; the reaction of (E)‐ BTE with a trace of water appears to be responsible for the chain initiation. The H₂SO₄‐catalyzed decomposition of diazoalkane 4 , indeed, produced the alkene 7 in high yield. The attack on the hindered diazoalkane 4 by 11 is slower than that by (E)‐ BTE ; the zwitterionic intermediate 21 undergoes cyclization and furnishes the tetrasubstituted furan 22 . In fumaronitrile, electrophilicity and steric demand are diminished, and a 1,3‐cycloaddition produces the 4,5‐dihydro‐1H‐pyrazole derivative 25 . The reaction of 4 with dimethyl acetylenedicarboxylate leads to pyrazole 29 +isobutene.     

Quinolone Analogs 13: Synthesis of Novel 1,1′‐(2‐Methylenepropane‐1,3‐diyl)di(4‐quinolone‐3‐carboxylate) and Related Compounds

The reaction of the 4‐hydroxyquinoline‐3‐carboxylate 6 with pentaerythritol tribromide gave the 1,1′‐(2‐methylenepropane‐1,3‐diyl)di(4‐quinolone‐3‐carboxylate) 11 , whose reaction with bromine afforded the 1,1′‐(2‐bromo‐2‐bromomethylpropane‐1,3‐diyl)di(4‐quinolone‐3‐carboxylate) 12 . Compound 12 was transformed into the (Z)‐1,1′‐(2‐acetoxymethylpropene‐1,3‐diyl)di(4‐quinolone‐3‐carboxylate) 13 or (E)‐1,1′‐[2‐(imidazol‐1‐ylmethyl)propene‐1,3‐diyl]di(4‐quinolone‐3‐carboxylate) 14 . Hydrolysis of the dimer (Z)‐ 13 or (E)‐ 14 with potassium hydroxide provided the (E)‐1,1′‐(2‐hydroxymethylpropene‐1,3‐diyl)di(4‐quinolone‐3‐carboxylic acid) 15 or (Z)‐1,1′‐[2‐(imidazol‐1‐ylmethyl)propene‐1,3‐diyl]di(4‐quinolone‐3‐carboxylic acid) 16 , respectively. The nuclear Overhauser effect (NOE) spectral data supported that those hydrolysis resulted in the geometrical conversion of (Z)‐ 13 into (E)‐ 15 or (E)‐ 14 into (Z)‐ 16 .     

`Inverse‐Electron‐Demand' Diels‐Alder Reactions of (E)‐3‐Diazenylbut‐2‐enes in Water

The cycloadditions of (E)‐3‐diazenylbut‐2‐enes 1 with a variety of alkenes 2 – 6 were carried out in water as well as in organic solvents. The reactions were always faster in heterogeneous aqueous medium than in the organic solvents. These conjugated diazenyl‐alkenes behave mainly as heterodienes, and the Diels‐Alder adducts are the sole or at least main reaction products. Pyrroles derived from zwitterionic [3+2] cycloaddition reactions were observed in some cases. The cycloaddition of 1a with (+)‐2‐(ethenyloxy)‐3,7,7‐trimethylbicyclo[4.1.0]heptane ( 5 ) is the first example of an asymmetric `inverse electron‐demand' Diels‐Alder reaction carried out in pure water.     

Electrophilic Reactivities of 1,2‐Diaza‐1,3‐dienes

The kinetics of the reactions of 1,2‐diaza‐1,3‐dienes 1 with acceptor‐substituted carbanions 2 have been studied at 20 °C. The reactions follow a second‐order rate law, and can be described by the linear free energy relationship log k(20 °C)=s(N+E) [Eq. (1)]. With Equation (1) and the known nucleophile‐specific parameters N and s for the carbanions, the electrophilicity parameters E of the 1,2‐diaza‐1,3‐dienes 1 were determined. With E parameters in the range of ?13.3 to ?15.4, the electrophilic reactivities of 1 a–d are comparable to those of benzylidenemalononitriles, 2‐benzylideneindan‐1,3‐diones, and benzylidenebarbituric acids. The experimental second‐order rate constants for the reactions of 1 a – d with amines 3 and triarylphosphines 4 agreed with those calculated from E, N, and s, indicating the applicability of the linear free energy relationship [Eq. (1)] for predicting potential nucleophilic reaction partners of 1,2‐diaza‐1,3‐dienes 1 . Enamines 5 react up to 10² to 10³ times faster with compounds 1 than predicted by Equation (1), indicating a change of mechanism, which becomes obvious in the reactions of 1 with enol ethers.     

Enantioselective Synthesis of Ethyl 4,5,7,8,9‐Penta‐O‐acetyl‐2,6‐anhydro‐ 3‐deoxy‐D‐erythro‐L‐gluca‐nononate: a 2‐Monodeoxygenated Derivative of `2‐Keto‐3‐deoxy‐D‐glycero‐D‐galacto‐nononic Acid'

A study aimed at developing an enantioselective synthesis of the title compound 23 , a 2‐monodeoxy analogue of the naturally occurring (+)‐2‐keto‐3‐deoxy‐D ‐glycero‐D ‐galacto‐2‐nononic acid (KDN), is reported. From D ‐mannose as starting material, the chiral 1,3‐diene 10 , activated by a silyloxy substituent at C(2), was prepared in six steps (Scheme 1). However, the intermediates were often contaminated with varying amounts of by‐products arising from overoxidation during cleavage with periodic acid. An alternative route starting from the inexpensive and readily available D ‐isoascorbic acid ( 12 ), though a little longer than the first, satisfactorily circumvented the purification problem and led to the desired dienes 17 in good yields (scheme 2). The [Co^II(S,S)‐(+)‐salen]‐catalyzed hetero‐Diels‐Alder reactions of the aforementioned dienes with ethyl glyoxylate proceeded smoothly at room temperature, giving the dihydropyrano adducts 18 in moderate yields (Scheme 3). Dihydroxylation of 18a followed by reduction of the keto function gave the desired 4,5‐trans dihydroxy moiety of the KDN framework (Scheme 4, see 21 ). The spectroscopic data of the penta‐O‐acetylated 2‐deoxy‐KDN ethyl ester 23 were consistent with those reported for the corresponding methyl ester derived from natural KDN.     

Amino‐Claisen Rearrangements and Diels‐Alder Reactions of Ketene N,O‐Acetals: Reactivity Studies. On the Way to a Novel Tandem Process?

We report the synthesis of N‐benzyl‐N‐[(E)‐buta‐1,3‐dienyl]propanamide ( 6 ) and its corresponding O‐silyl‐substituted ketene N,O‐acetal 7 and their Diels‐Alder reaction. Propanamide 6 reacted smoothly, whereas the yield obtained from 7 was low, probably due to polymerization of the dienophile induced by electron transfer. The ketene N,O‐acetals 27a – g were synthesized starting from the corresponding benzamides 25a – e (Scheme 9). The ketene N,O‐acetals 27a – g showed increased stabilities and underwent amino‐Claisen rearrangements under thermal conditions. Using catalysts, interesting side reactions leading either to the annulated systems rac‐ 35 – 37 or to a β‐lactam rac‐ 34 were observed.     

1,2,3‐Trimethoxy‐4‐[(E)‐2‐phenylvinyl]benzene and (E,E)‐1,4‐bis(2,3,4‐trimethoxyphenyl)buta‐1,3‐diene

The stilbene derivative 1,2,3‐trimethoxy‐4‐[(E)‐2‐phenylvinyl]benzene, C₁₇H₁₈O₃, (I), and its homocoupling co‐product (E,E)‐1,4‐bis(2,3,4‐trimethoxyphenyl)buta‐1,3‐diene, C₂₂H₂₆O₆, (II), both have double bonds in trans conformations in their conjugated linkages. In the structure of stilbene (I), the aromatic rings deviate significantly from coplanarity, in contrast with coproduct (II), the core of which is rigorously planar. The deviation in stilbene (I) seems to be driven by intermolecular electrostatic interactions. Diene (II) sits on a crystallographic inversion centre, which bisects the conjugated linkage.     

One‐Pot,Asymmetric and Diastereoselective Four‐Component Synthesis of Polyfunctional (Z)‐Alkenyl Methyl Sulfones with Three Stereogenic Centers

The reaction of 1‐(trimethylsilyloxy)cyclopentene ( 9 ) with (±)‐1,3,5‐triisopropyl‐2‐(1‐(RS)‐{[(1E)‐2‐methylpenta‐1,3‐dienyl]oxy}ethyl)benzene ((±)‐ 4a ) in SO₂/CH₂Cl₂ containing (CF₃SO₂)₂NH, followed by treatment with Bu₄NF and MeI gave a 3.0 : 1 mixture of (±)‐(2RS)‐2{(1RS,2Z,4SR)‐2‐methyl‐4‐(methylsulfonyl)‐1‐[(RS)‐1‐(2,4,6‐triisopropylphenyl)ethoxy]pent‐2‐en‐1‐yl}cyclopentanone ((±)‐ 10 ) and (±)‐(2RS)‐2‐{(1RS,2Z)‐2‐methyl‐4‐[(SR)‐methylsulfonyl]‐1‐[(SR)‐1‐(2,4,6‐triisopropylphenyl)ethoxy]pent‐2‐en‐1‐yl}cyclopentanone ((±)‐ 11 ). Similarly, enantiomerically pure dienyl ether (−)‐(1S)‐ 4a reacted with 1‐(trimethylsilyloxy)cyclohexene ( 12 ) to give a 14.1 : 1 mixture of (−)‐(2S)‐2‐{(1S,2Z,4R)‐2‐methyl‐4‐(methylsulfonyl)‐1‐[(S)‐1‐(2,4,6‐triisopropylphenyl)ethoxy]pent‐2‐enyl}cyclohexanone ((−)‐ 13a ) and its diastereoisomer 14a with (1S,2R,4R) or (1R,2S,4S) configuration. Structures of (±)‐ 10 , (±)‐ 11 , and (−)‐ 13a were established by single‐crystal X‐ray crystallography. Poor diastereoselectivities were observed with the (E,E)‐2‐methylpenta‐1,3‐diene‐1‐ylethers (+)‐ 4b and (−)‐ 4c bearing ( 1 S )‐1‐phenylethyl and (1S)‐1‐(pentafluorophenyl)ethyl groups instead of the Greene's auxiliary ((1S)‐(2,4,6‐triisopropylphenyl)ethyl group). The results demonstrate that high α/β‐syn and asymmetric induction (due to the chiral auxiliary) can be obtained in the four‐component syntheses of the β‐alkoxy ketones. The method generates enantiomerically pure polyfunctional methyl sulfones bearing three chiral centers on C‐atoms and one (Z)‐alkene moiety.