64489-06-1Relevant academic research and scientific papers
Simple and efficient synthesis of the acetylene equivalent (E)-1-benzenesulfonyl-2-(trimethylsilyl)ethylene
Grigg, Ronald,Najera, Carmen,Sansano, Jose M.,Yus, Miguel
, p. 1111 - 1114 (1997)
The acetylene equivalent (E)-1-benzenesulfonyl-2-(trimethylsilyl)ethylene is readily synthesized in a one-pot reaction, in excellent yield under very mild reaction conditions, via iodosulfonylation-dehydroiodination of vinyltrimethylsilane.
1-(Phenylsulfonyl)-2-(trimethylsilyl)ethane: A Valuable Intermediate for Synthesis of Olefins, Allyltrimethylsilanes, β-Trimethylsilyl Ketones, Vinyl Sulfones, 2-(Phenylsulfonyl)allyl Alcohols, and Varied Trimethylsilyl Derivatives
Hsiao, C.-N.,Shechter, H.
, p. 2688 - 2699 (2007/10/02)
1-(Phenylsulfonyl)-2-(trimethylsilyl)ethane (1), prepared from 1-(trimethylsilyl)-2-(thiophenoxy)ethane and hydrogen peroxide, is converted by n-butyllithium to 1-(phenylsulfonyl)-1-lithio-2-(trimethylsilyl)ethane (2).Primary halides effect alkylation of 2 to 2-(phenylsulfonyl)-1-(trimethylsilyl)alkanes (3), reactions of which with n-butyllithium and then primary halides give higher 2-(phenylsulfonyl)-1-(trimethylsilyl)alkanes (5).Debenzenesulfonyltrimethylsilylation of 3 and 5 occurs efficiently with tetra-n-butylammonium fluoride (6) to yield mono- and disubstituted terminal olefins (7 and 8, respectively). 2-(Phenylsulfonyl)-3-(trimethylsilyl)-1-alkanols (14) result from reactions of 2 with aldehydes and ketones and then acidification.Allyltrimethylsilanes (18) are obtained by reductive elimination of mesylates (17) of 14 with sodium amalgam in methanolic disodium hydrogen phosphate. 2-(Phenylsulfonyl)-3-(trimethylsilyl)-1-propene (23), a 1-cationic-2-anionic equivalent (33), is preparable by (1) condensation of 1 and formaldehyde to 2-(phenylsulfonyl)-3-(trimethylsilyl)-1-propanol (24), (2) conversion of 24 by triphenylphosphine/carbon tetrachloride to 1-chloro-2-(phenylsulfonyl)-3-(trimethylsilyl)propane (25), and (3) elimination of 25 with triethylamine. β-Trimethylsilyl ketones (35) are produced by sodium amalgam reduction of α-phenylsulfonyl β-trimethylsilyl ketones (34) obtained by oxidation of 2-(phenylsulfonyl)-3-(trimethylsilyl)-1-propanols (14, R2 = H) with chromic acid sulfonic acid in acetone.Acidification of the adducts from 2 and epoxides yields 3-(phenylsulfonyl)-4-(trimethylsilyl)-1-butanols (38).Primary and secondary alcohols 38 are converted by chromic acid/sulfuric acid to 3-phenyl sulfonyl 4-trimethylsilyl aldehydes and ketones (39). n-Butyllithium effects cyclization of methanesulfonates (40) of 37 to 1-(phenylsulfonyl)-1-cyclopropanes (42) with displacement of lithium methanesulfonate. 1-(Phenylsulfonyl)-2-n-hexyl-1-cyclopropane (46a) and 1-(phenylsulfonyl)-2-phenyl-1-cyclopropane (46b) are eliminated by 6 to 1-n-hexyl-2-methylenecyclopropane (47a) and 1-methylene-2-phenylcyclopropane (47b), respectively. 2-(Phenylsulfonyl)-1-alkenes (49) are prepared by reactions of 6 with 2-(phenylsulfonyl)-2-chloro-1-(trimethylsilyl)alkanes (48) obtained (1) from tert-butyl hypochlorite and 2-(phenylsulfonyl)-2-lithio-1-(trimethylsilyl)alkanes(4) and/or (2) by reaction of 1-(phenylsulfonyl)-1-chloro-2-(trimethylsilyl)ethane (50) with n-butyllithium and alkylations of the resulting 1-(phenylsulfonyl)-1-chloro-1-lithio-2-(trimethylsilyl)ethane (51).Synthesis of 50 is best effected by base-catalyzed cleavage of 3-(phenylsulfonyl)-3-chloro-4-(trimethylsilyl)-2-butanone (54) prepared from 1-acetyl-1-phenylsulfonyl)-2-(trimethylsilyl)ethane (53) and ...
Sulfone reagents in organic synthesis. VI. Sulfonyl- and silyl-substituted hydrocarbons as versatile carbanion precursors in organic synthesis
Eisch, John J.,Behrooz, Mohammad,Dua, Suresh K.
, p. 121 - 136 (2007/10/02)
The basic organometallic chemistry of β-silyl-substituted acetylenic, vinylic and alkyl sulfones has been investigated, with attention being given to metallation, carbometallation and the chemical reduction of carbon-carbon unsaturation. 2-Trimethylsilylvinyl and 2-trimethylsilylalkyl sulfones underwent smooth and stereoselective lithiation with RLi on the carbon α to the sulfonyl group. Carbometallation of vinyl sulfones could be achieved with RMgX or LiCuR2, but acetylenic sulfones carbometallated smoothly only with LiCuR2; with RMgX or RLi, these acetylenes underwent alkyldesulfonylation. The utility in synthesis of these metallo derivatives of sulfonyl-silyl-hydrocarbons is discussed and their value in elaborating carbon skeletons is illustrated for the preparation of alkenes, allenes, carbocycles and stereo-defined vinyl sulfones.
Dienophilic Properties of Phenyl Vinyl Sulfone and trans-1-(Phenylsulfonyl)-2-(trimethylsilyl)ethylene. Their Utilization as Synthons for Ethylene, 1-Alkenes, Acetylene, and Monosubstituted Alkynes in the Construction of Functionalized Six-Membered Rings via ? Cycloaddition Meth.
Carr, Richard V. C.,Williams, Richard V.,Paquette, Leo A.
, p. 4976 - 4986 (2007/10/02)
Useful procedures for effecting the indirect capture of ethylene, acetylene, 1-alkenes, and monosubstituted alkynes in Diels-Alder cycloadditions have been developed.In the first sequence, phenyl vinyl sulfone is shown to enter into ? reactions as a moderately reactive dienophile and to do so with very good regioselectivity.The resulting adducts can be directly desulfonated or alkylated prior to such reduction.A wide range of functional groups can be appended in this fashion at a specific locus within the newly formed six-membered ring.When the analogous chemistry is applied to trans-1-(phenylsulfonyl)-2-(trimethylsilyl)ethylene (2), adducts result which undergo ready fluoride ion induced elimination with efficient introduction of a double bond.The use of 2 and its d2 derivative is highlighted by the synthesis of several functionalized dibenzobarrelenes.
NEW METHOD FOR REGIOSELECTIVE SYNTHESIS OF α-SUBSTITUTED ALLYLSILANES AND ITS APPLICATION TO THE SYNTHESIS OF E- AND Z-TAGETONES
Ochiai, Masahito,Sumi, Kenzo,Fujita, Eiichi,Tada, Shin-ichi
, p. 3346 - 3349 (2007/10/02)
Sequential addition of lithium salt of carbanion and tributylstannylmethyl iodide (3) to vinyl sulfone 2 afforded β-tributylstannyl sulfones 5, which gave substituted allylsilanes 1 in a regioselective manner by the smooth destannylsulfonation.Allylsilane 8 prepared by Michael type addition of isopropenyllithium to 2 was converted into tagetones (10). Keywords --- allylsilane; β-trimethylsylilvinyl sulfone; destannylsulfonation; tributylstannylmethyl iodide; tagetone; Michael addition
An Indirect Method for Engaging Unactivated Alkenes as Effective Dienophiles in Regioselective Diels-Alder Reactions
Paquette, Leo A.,Crouse, Gary D.
, p. 141 - 142 (2007/10/02)
Terminal alkenes and cyclic olefins can be made to enter into efficient, regiocontrolled Diels-Alder cycloaddition by prior selenosulfonation and oxidation to the vinyl sulfone.Reductive desulfonation after condensation with an activated diene provides th
Regiocontrolled Synthesis of Mono-, Di, and Trisubstituted Cyclohexenones by Cycloaddition of Vinyl Sulfones to 1-Methoxy-3--1,3-butadienes. Conversion of Alkenes into Effective Dienophilic Reagents
Kinney, William A.,Crouse, Gary D.,Paquette, Leo A.
, p. 4986 - 5000 (2007/10/02)
Cycloaddition of phenyl vinyl sulfone to Danishefky's diene followed by direct ketalization provided 7, a synthon for the 4-(2-cyclohexenyl) anion.Thus, 7 readily undergoes regiospecific γ-alkylation.Ensuing reductive desulfonylation and hydrolysis provides 2-(and 3-)-cyclohexenones efficiently.Zingiberenol, a monocyclic sesquiterpene, was prepared by means of this methodology.Terminal alkenes and cyclic olefins enter into comparable regiocontrolled Diels-Alder addition if they are first subjected to selenosulfonation and oxidation to the vinyl sulfone.Removal of the phenylsulfonyl substituent after condensation provides the adducts which are formally derived from alkylation of the hypothetical C5 anion of 2-cyclohexenone.The scheme can be expanded to include γ-alkylation prior to desulfonylation.By this means, one is able to prepare 4,5-disubstituted 2-(and 3-)cyclohexenones where the nature of the pendant side chains can be widely varied.
SILICON IN ORGANIC SYNTHESIS. 12. trans-1-BENZENESULFONYL-2-(TRIMETHYLSILYL)ETHYLENE, A DIELS-ALDER DIENOPHILE EQUIVALENT OF ACETYLENE AND MONOSUBSTITUTED ACETYLENES
Paquette, Leo A.,Williams, Richard V.
, p. 4643 - 4646 (2007/10/02)
trans-1-Benzenesulfonyl-2-(trimethylsilyl)ethylene and its 1,2-d2 derivative enter into Diels-Alder cycloaddition to give products which are smoothly eliminated with fluoride ion.Alkylation of the α-sulfonyl carbanion can precede elimination, s
