1,3-Dithiane

• Catalog No.: A10505
• CAS Number: 505-23-7
• M. F.: C4H8S2
• M. W.: 120.23632
• Purity: 98%

SYNONYMS

• Title: 1,3-二噻烷
• IUPAC name: 1,3-dithiane
• IUPAC Traditional name: 1,3-dithiane

DATABASE IDS

• MDL Number: MFCD00006654
• CAS Number: 505-23-7
• Beilstein Number: 102534
• EC Number: 208-006-7

PROPERTIES

• Purity: 98%
• Boiling Point: 207-208°C
• Flash Point: 90°C(194°F)
• Melting Point: 52-55°C
• RTECS: JO5070000
• TSCA Listed: 否
• Hazard Class: 9
• UN Number: UN3335
• Packing Group: III

REFERENCES

• Chloramine-T: Synth. Commun., 2, 7 (1972); NCS, AgNO₃, acetonitrile-water: J. Org. Chem., 36, 3553 (1971); 48, 1552 (1983); SO₂Cl₂, silica, DCM-water: Synthesis, 678 (1976); Bromodimethylsulfonium bromide (from DMSO and bromine): Synthesis, 720 (1979); DMSO-HCl-dioxane: Synthesis, 679 (1982); CuCl₂, CuO, acetone: Org. Synth. Coll., 6, 109 (1988); CAN, acetonitrile-water: Synth. Commun., 11, 423 (1981); DDQ, acetonitrile-water: J. Chem. Soc., Perkin 1, 453 (1996); Phenyl phosphorodichloridate, NaI, acetonitrile-DMF: Tetrahedron Lett., 29, 5471 (1988); Glyoxylic acid in AcOH: Synthesis, 694 (1976); HIO₄, THF-ether: Tetrahedron Lett., 37, 4331 (1996); PhI(OAc)₂, acetone-water: Syn. Commun., 30, 4081 (2000). For facilitation of cleavage of 1,3-dithianes by S-alkylation, see Trimethyloxonium tetrafluoroborate, A15175.
• The 2-lithio derivative, normally generated with n-BuLi, behaves as a formyl anion equivalent. It has been shown that the rigorous exclusion of atmospheric oxygen minimizes side reactions and is critical in obtaining optimum results in these lithiation procedures: J. Org. Chem., 60, 4258 (1995).
• Monoalkylation of the 2-lithio-derivative and cleavage of the dithiane leads to an aldehyde. Successive dialkylation provides a route to ketones. For reviews of the reversal of the normal reactivity of groups, "umpolung", see: Angew. Chem. Int. Ed., 18, 239 (1979), and of the umpolung of carbonyl activity through sulfur-containing reagents: Synthesis, 357 (1977). See also 1,3-Propanedithiol, A15261, 1,3-Dithiolane, L11914, and 1,2-Ethanedithiol, L12865.
• Reaction with 2-cyclohexenone proceeds via 1,2-addition. For details of this and subsequent cleavage and rearrangement, see: Org. Synth. Coll., 8, 309 (1993):
  
• For conversion to the dithienium salt by hydride abstraction, see Triphenylcarbenium tetrafluoroborate, A12949.
• Reviews: Synthetic uses of 1,3-dithianes: Tetrahedron, 45, 7643 (1989); Chemistry of 1,3-dithioacetals: Organosulfur Chemistry, P. Page, Ed., Academic Press N.Y. (1995).
• For an example of successive acylation and alkylation of 1,3-dithiane, which can be carried out as a one-pot sequence, see: Synthesis, 625 (1980).
• Cleavage of 1,3-dithianes has been effected by a variety of methods, including: