The Chemistry of Ylids. VI. Dimethylsulfonium Fluorenylide—A

DIMETHYLSULFONIUM FLUODNYLIDE

Jan. 20, 1961

[CONTRIBUTION FROM

The Chemistry of Ylids. BY A.

THE

417

MELLONINSTITUTE, PITTSBURGH 13, PENNA.]

VI.

Dimethylsulfonium Fluorenylide-A Epoxides1 WILLIAMJOHN SON^ AND ROBERTB. LACOUNT

Synthesis of

RECEIVED JULY 25, 1960 An attempt to effect a Wittig reaction between 9-dimethylsulfonium fluorenylide (Ira) and benzaldehydes to form B-benzalfluorenes has instead led to the formation of benzalfluorene oxides (VIII) and phenyl-9-( 1-methylthiomethy1)-fluorenylcarbinols (X). A pronounced solvent effect operates in this reaction. Nitrosobenzene with IIa gave N-phenylfluorenone ketoxime (XIV). The sulfur ylid IIa has been shown to be less reactive than the corresponding phosphorus (IIb,c,d) and arsenic (IIe) derivatives as was expected from its physical properties.

Introduction Although the reaction between 'onium ylids (I) and carbonyl compounds to form olefins (Wittig reaction) has been known for forty year^,^ its potential has been explored and realized only within the last few years4 In all previous examples of its use in organic syntheses the 'onium group X has been triphenylpho~phonium~ (I, X = (CeHd3P)

%-e