1,1-Bis(phenylsulfonyl)ethylene1

[39082-53-6]  · C14H12O4S2  · 1,1-Bis(phenylsulfonyl)ethylene  · (MW 308.37)

(powerful Michael acceptor and dienophile; reagent for two-carbon homologation of ketones; synthetic equivalent of ethylene in Diels-Alder reactions and of ethylene 1,2-dipole in cycloadditions)1

Alternate Name: 1,1-BPSE.

Physical Data: mp 124-126 °C.

Form Supplied in: colorless solid.

Analysis of Reagent Purity: depending upon the method of preparation, it may contain bis(phenylsulfonyl)methane and 1,1,3,3-tetrakis(phenylsulfonyl)propane as impurities. In a few cases, isomerization to (E)-1,2-bis(phenylsulfonyl)ethylene has been observed.2,3a The chemical shift of the vinyl protons is 7.19 ppm (CDCl3).

Preparative Methods: the reagent can be prepared via careful oxidation of the corresponding ketene dithioacetal3a or via Mannich condensation of bis(phenylsulfonyl)methane with paraformaldehyde and a secondary amine followed by elimination with acids.3

Handling, Storage, and Precautions: keep dry and refrigerated; potential alkylating agent; use in a fume hood.

Addition Reactions.

The two geminal phenylsulfonyl groups impart to the double bond of 1,1-BPSE a strong electrophilic nature which manifests most evidently in Michael additions.1b Heteroatomic nucleophiles such as amines, alcohols, and thiols add in nonpolar solvents even without added base.1b,3a Water, either under acid or base catalysis, and strong nucleophiles in protic solvents can cleave the double bond with eventual formation of 1,1,3,3-tetrakis(phenylsulfonyl)propane.1b,4 1,1-BPSE adds to carbon nucleophiles generated from active methylene compounds using different bases5 (eq 1),5d including fluoride ions,5d or under Lewis acid catalysis.5a Neutral carbon nucleophiles6 such as enol ethers (eq 2)6c and enamines6a also add smoothly with no need of extra activation. Enantiomerically pure enamino esters give, after hydrolysis, ketones which display stereochemistry opposite to that obtained with Phenylsulfonylethylene (eq 3).6d Ynamines react similarly, but in this case the likely zwitterionic intermediate cyclizes to a [2 + 2] cycloadduct (eq 4).7

Enolizable ketones and imines also react with 1,1-BPSE even without base catalysis.6 Since the nucleophile is presumably the enol, the regiochemistry of the addition is opposite to that obtained with enolates (eq 5).6b

Cycloadditions.

The title reagent forms Diels-Alder adducts with dienes such as 1,3-cyclohexadiene (1),8a,b cycloheptatriene (2),8a norbornadiene (3),6a,8c quadricyclane (4),6a,8a,c 2-acetoxy-1,3-cyclopentadiene (5),8a and N-benzoylindole-2,3-quinodimethane (6).8d In cases where two regioisomers can form, the results are in accordance with the stereochemistry expected on the basis of orbital coefficients.8a,d

Due to the polarization of the reagent, [2 + 2] cycloadducts and products arising from dipolar rearrangements have been observed in reactions with strained alkenes. Benzonorbornadiene is an example (eq 6).6a The desulfonylation reaction can be performed with Aluminum Amalgam or Sodium Amalgam in such a way as to obtain sequential mono- and bisdesulfonylation (see also 1,2-Bis(phenylsulfonyl)ethylene).

Chiral variants of the title reagent having a 2,2-binaphthyl residue in the place of the two phenyl rings have been proposed (see 1,1-Binaphthalene-2,2-dithiol).9


1. (a) Neplyuev, V. M.; Bazarova, I. M.; Lozinskii, M. O. RCR 1986, 55, 883. (b) De Lucchi, O.; Pasquato, L. T 1988, 44, 6755. (c) Simpkins, N. S. In Sulphones in Organic Synthesis; Pergamon: Oxford, 1993.
2. Neplyuev, V. M.; Bazavova, I. M. ZOR 1981, 17, 2231.
3. (a) Carpino, L. A. JOC 1973, 38, 2600. (b) Stetter, H.; Steinbeck, K. LA 1974, 1315.
4. Bazavova, I. M.; Neplyuev, V. M.; Lozinkii, M. O. ZOR 1983, 19, 83.
5. (a) Neplyuev, V. M.; Lozinskii, M. O. ZOR 1981, 17, 2232. (b) Bazavova, I. M.; Neplyuev, V. M.; Lozinskii, M. O. ZOR 1982, 18, 865. (c) Rao, K. Y.; Nagarajan, M. IJC(B) 1983, 22B, 519. (d) Bazavova, I. M.; Neplyuev, V. M. UKZ 1983, 49, 758. (e) Baker, W. R.; Condon, S. L.; Spanton, S. TL 1992, 33, 1573.
6. (a) De Lucchi, O.; Pasquato, L.; Modena, G. TL 1984, 25, 3643. (b) De Lucchi, O.; Pasquato, L.; Modena, G. TL 1984, 25, 3647. (c) Obrecht, D. HCA 1991, 74, 27. (d) Pinheiro, S.; Guingant, A.; Desmaële, D.; d'Angelo, J. TA 1992, 3, 1003.
7. (a) Himbert, G.; Kosack, S. CB 1988, 121, 2053. (b) Himbert, G.; Faul, D. TL 1988, 29, 5355.
8. (a) De Lucchi, O.; Lucchini, V.; Pasquato, L.; Zamai, M.; Modena, G. G 1984, 114, 293. (b) Rao, Y. K.; Nagarajan, M. S 1984, 757. (c) Paquette, L. A.; Kesselmayer, M. A.; Künzer, H. JOC 1988, 53, 5185. (d) Haber, M.; Pindur, U. T 1991, 47, 1925.
9. (a) De Lucchi, O.; Fabbri, D.; Lucchini, V. SL 1981, 565. (b) De Lucchi, O.; Fabbri, D.; Lucchini, V. T 1992, 48, 1485.

Ottorino De Lucchi

Università di Venezia, Italy

Lucia Pasquato

CNR-CMRO, Padova, Italy



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