Title: Lawesson's Reagent
CAS Registry Number: 19172-47-5
CAS Name: 2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide
Synonyms: anisyldithiophosphinic anhydride
Molecular Formula: C14H14O2P2S4
Molecular Weight: 404.47
Percent Composition: C 41.57%, H 3.49%, O 7.91%, P 15.32%, S 31.71%
Literature References: Thionating agent for conversion of carbonyls to thiocarbonyls. Prepn: H. Z. Lecher
et al., J. Am. Chem. Soc. 78, 5018 (1956); and delineation of use: B. S. Pedersen
et al., Bull. Soc. Chim. Belg. 87, 223 (1978); S. Scheibye
et al., ibid., 229. Mechanistic study: T. B. Rauchfuss, G. A. Zank,
Tetrahedron Lett. 27, 3445 (1986). Use in thionations: A. Z.-Q. Khan, J. Sandstr?m,
J. Chem. Soc. Perkin Trans. 1 1988, 2085; S. Araki
et al., Bull. Chem. Soc. Jpn. 61, 2977 (1988); as reducing agent for sulfoxides: H. Bartsch, T. Erker,
Tetrahedron Lett. 33, 199 (1992). Review of thionation reactions: M. P. Cava, M. I. Levinson,
Tetrahedron 41, 5061-5087 (1985); of applications in organic and organometallic syntheses: M. Jesberger
et al.,
Synthesis 2003, 1929-1958.
Properties: mp 229°, should be stored under anhydrous conditions.
Melting point: mp 229°
Use: Thiation reagent.