4440-32-8

Upstream product

• 76256-16-1 2'-methyl-3'-phenylfluorene-9-spiro-4'-(1',2'-thiazolidine)-5'-spiro-9-fluorene 1'-oxide 
• 1141-08-8 4,4'-dimethylthiobenzophenone 
• 197901-71-6 9-fluorenyl trichloromethyl sulfoxide 
• 79310-05-7 3',6'-dihydro-3',5',6'-triphenylspiro(fluorene-9,2'-<1,3,4>thiadiazine) 1'-oxide 
• 830-72-8 9H-fluorene-9-thione 
• 106864-89-5 methyl 9-fluorenesulfinate 
• 132020-45-2 di-9-fluorenyl sulfoxide 
• 75-77-4 chloro-trimethyl-silane 
• 86-73-7 9H-fluorene 

Downstream Products

• 64874-48-2 3'-phenylspirooxathiazole> 5'-oxide 
• 50999-08-1 3',5'-diphenyl-3'H-spiro[fluorene-9,2'-[1,3,4]thiadiazole] 1'-oxide 
• 4427-65-0 1,2,3,4,5,6,8,9,10,11,12,13-dodecahydrodicycloocta[1,4]dithiin 
• 486-25-9 9-fluorenone 
• 81817-38-1 [RhCl(P(C₆H₁₁)3)2(C₁₂H₈CSO)] 
• 75701-23-4 bis(triphenylphosphine)(9-sulfinylfluorene)platinum⁽⁰⁾*0.5benzene 
• 75170-21-7 (fluorenylidenesulfine)bis(triphenylphosphine)palladium⁽⁰⁾ 
• 76256-17-2 3'-methyl-4'-phenylfluorene-9-spiro-2'-(1',3'-thiazolidine)-5'-spiro-9-fluorene 1'-oxide 
• 80961-33-7 [IrCl(P(C₆H₁₁)3)2(C₁₂H₈CSO)] 
• 50999-12-7 3',5'-diphenyl-3'H-spiro[fluorene-9,2'-[1,3,4]thiadiazole] 1',1'-dioxide 
• 79310-06-8 cis-2',5'-dihydro-2',4',5'-triphenylspiro(fluorene-9,6'-<1,2,3>thiadiazine) 1'-oxide 
• 79310-06-8 trans-2',5'-dihydro-2',4',5'-triphenylspiro(fluorene-9,6'-<1,2,3>thiadiazine) 1'-oxide 
• 746-47-4 tetrabenzo[5.5]fulvalene 
• 6596-81-2 1,3-dimethylimidazole-2-thione 

Relevant academic research and scientific papers

Study of Reactions Leading to Sulfine Formation. 6. Base-Catalyzed Decomposition of Di-9-fluorenyl Sulfoxide

When treated with CH3ONa in CH3OH-CH2Cl2, di-9-fluorenyl sulfoxide (3) undergoes elimination readily to afford 9-thiofluorenone S-oxide (4) and fluorene (eq 2).Comparison of the rate of the elimination to the rate of disappearance in the presence of CD3OD of the 1H NMR signal for the 9-H in 3 shows that the mechanism of this sulfine-forming elimination is (E1cB)rev, the rate of cleavage of the intermediate α-sulfinyl carbanion 7 to give 4 and a 9-fluorenyl carbanion being over 100 times slower than the rate at which 7 is protonated to regenerate 3.The (E1cB)rev behavior of this elimination is contrasted with the (E1cB)rev/(E1cB)irrev borderline behavior of the elimination of diarylmethyl (arylmethyl)sulfonyl sulfoxides 1, and a reason for this at first sight unexpected difference in behavior is presented.

Synthesis of mono- and disubstituted sulfines via β-elimination of chloroform from trichloromethyl sulfoxides

A new method for the synthesis of thioaldehyde and thioketone S-oxides by an unusual base-induced β-elimination of chloroform from readily available allylic and benzylic trichloromethyl sulfoxides is described. The reaction proceeds smoothly under mild conditions. The facile preparation of α,β-unsaturated sulfines by the new method is of special interest. A possible mechanism for this remarkable sulfine synthesis and apparently unprecedented β-elimination of chloroform is presented.

Rates of H/D Exchange of 9-Fluorenyl Sulfoxides: Evidence for an Irreversible E1cB Mechanism for Base-Induced Sulfine Formation from Methyl Diarylmethanesulfinates

A previous study had shown that the base-catalyzed, sulfine-forming eliminations of methyl 9-fluorenesulfinate (4) and other methyl diarylmethanesulfinates take place by either an E1cB-irreversible or an E2 mechanism, rather than the E1cB-reversible mechanism that had been expected.In the present work the rates (kexch) of DABCO (diazacyclooctane)-catalyzed H/D exchange of the 9-H in a series of 9-fluorenyl sulfoxides (3) have been determined at 25 deg C in CD3OD.From a plot of log kexch vs ?* for R in 3 the anticipated rate for the DABCO-catalyzed formation ofthe 9-fluorenyl carbanion from 4 (eq 3, R = OCH3) can be estimated.Comparison of this rate with the actual rate (kelim) of the DABCO-catalyzed, sulfine-forming elimination of 4 (eq 5) indicates that the elimination does not take place by an E2 mechanism in which there is a significant degree of cleavage of the S(O)-OCH3 bond in the rate-determining transition state.The results are, however, entirely consistent with an E1cB-irreversible mechanism for the elimination.

Elimination Reactions of Alkanesulfinyl Derivatives: Mechanism and Reactivity in Base-Induced Sulfine Formation from Methyl Diarylmethanesulfinates

Upon treatment in methanol at room temperature with methoxide ion methyl diarylmethanesulfinates, ArAr'CHS(O)OCH3 (1), and methyl 9-fluorenesulfinate (2) undergo elimination readily to afford the corresponding sulfines (3 and 4) in quantitative yield.Studies in CD3O-/CD3OD show that, surprisingly, elimination of 1 to give 3 is significantly faster than nucleophilic substitution by methoxide ion at the sulfinyl group (exchange of CH3O by CD3O).Even more unexpected, the kinetic isotope effect for elimination of 2-9-d (kH/kD=6.1) and absence of detectable H/D exchange of the methine proton of 1 in CD3OD prior to sulfine formation extablish that, even though the leaving group is MeO-, the elimination takes place by either an irreversible ElcB or an E2 mechanism, rather than the reversible ElcB mechanism found (ref 4 and 7) for the analogous sulfene-forming elimination of arylmethanesulfonate esters with oxyanion leaving groups of comparable pKa.Reaction of amines with 2 in methanol also gives sulfine 4, and the amine-induced elimination, which has a large Broensted β, also proceeds by either an (ElcB)irrev or an ElcB-like E2 mechanism.Why sulfine-forming eliminations of 1 and 2 favor an (ElcB)irrev or E2 mechanism whereas sulfene-forming eliminations of arylmethanesulfonates with even better leaving groups proceed by an (ElcB)rev mechanism is considered and a possible explanation presented.

Preparation of sulfines by alkylidenation of sulfur dioxide using α-silyl carbanions

The synthesis of sulfines 4 from a series of active methylene compounds is described.Deprotonation, followed by silylation, gives the trimethylsilyl compounds 2.Subsequent deprotonation to α-silyl carbanions and treatment with an excess of sulfur dioxide

Cycloaddition Reactions of Sulphines and Thiones with Azoalkenes

Fluorenethione S-oxide undergoes (2+4) cycloadditions with azoalkenes to yield 2H-1,2,3-thiadiazine 1-oxides together with a small amount of the regioisomeric 6H-1,3,4-thiadiazine 1-oxides.Fluorenethione, with azoalkenes, undergoes (2+4) regiospecific cycloaddition reactions leading to the formation of 6H-1,3,4-thiadiazine derivatives.Diarylsulphines and diarylthiones fail to react with azoalkenes.

CYCLO-ADDITION REACTIONS OF THIOFLUORENONE WITH NITRONES

Thiofluorenone reacts with C-phenyl-N-methylnitrone to give, initially, a 1,2,5-oxathiazolidine.Spontaneous loss of sulphur monoxide then produces a dipolar species which reacts with a second molecule of thiofluorenone to give a 1,2-thiazolidine.This thiazolidine partially isomerizes to a 1,3-thiazolidine on heating.The corresponding 1,2-thiazolidine 1-oxide similarly undergoes a cycloreversion-recyclization reaction to the isomeric 1,3-thiazolidine 1-oxide.The reaction of thiofluorenone with C-phenyl-N-phenylnitrone gives a 1,2-thiazetidine 1-oxide, a benzothiazine S-oxide, and a thiazolidine.The formation of the first two products can be explained by involving a rearrangement of the primary 1:1 adduct; the last product may derive from the same adduct by loss of sulphur monoxide followed by a reaction with a second molecule of thione.