New synthetic reactions.  New approach to geminal alkylation

Trost, Barry M.; Preckel, Margaret M.

doi:10.1021/ja00804a051

Cited by 34 publications

(7 citation statements)

References 2 publications

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“…The alcohol 14a was obtained in 43-65% yield; v,,, (CHC1,) 3640,3490 cm-'; 6 (CDC1,) 10H,3,4,5,6,OH),3.46 (d,2H, J = 5.4 HZ; CH2-OH), 3.89 (s,4H;0CH2CH20). This alcohol was converted into the crystalline 4-(4-nitro)phenylazo benzoate 15a for analysis in the manner described below.…”

Section: Conversion Of 4a and 4b Into The Alcohols I4a And I4b ( A ) mentioning

confidence: 96%

N-Nitromethylphthalimide. A formyl anion equivalent

Cowherd¹,

Doria²,

Galeazzi³

et al. 1977

Can. J. Chem.

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It is shown that the exclusive 1,4-addition of N-nitromethylphthalimide 4a to unhindered α,β-unsaturated ketones and esters can be effected by non-nucleophilic bases, such as sodium hydride or potassium fluoride, in dimethyl sulfoxide. The phthalimido moiety can be removed from the adducts with hydroxylamine or 1,2-dianilinoethane to give the oximes or diphenylimidazolidines of 1,4-ketoaldehydes. The ethylene ketal 5 of 3-formylcyclohexanone could easily be recovered from the imidazolidine 10, but it was not possible to transform 11 into 3-formylcyclohexanone under similar conditions. It is further shown that reactions, such as the Knoevenagel condensation, or the Paal–Knorr synthesis of pyrroles, can be achieved directly on the adducts without the need for isolating the unstable 4-formyl carbonyl compounds. N-Nitromethylphthalimide thus serves as a new formyl anion equivalent.

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Section: Conversion Of 4a and 4b Into The Alcohols I4a And I4b ( A ) mentioning

confidence: 96%

N-Nitromethylphthalimide. A formyl anion equivalent

Cowherd¹,

Doria²,

Galeazzi³

et al. 1977

Can. J. Chem.

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“…(11.17)- ( 11.19). These reactions represent important steps in routes to disaccharides, (516) desoxypodocarpate, (517) and grandisol, (518) respectively. o <O~~_QAe.…”

Section: Aliphatic Aldehydesmentioning

confidence: 99%

Carbonylation

Colquhoun¹,

Thompson²,

Twigg³

1991

236

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“…Cycloaddition Reactions of 1 with Olefins 2 and with Imines 6. In the presence of excess cyclopentadiene (2a) at - 15 °C, the ketene 1 generated in situ by dehydrochlorination of a-(phenylthio)propanoyl chloride with triethylamine af-0022-3263/79/1944-2067$01.00/0 © 1979 American Chemical Society 85.0-85.5 0 Isolated yield. 6 n-Hexane reaction solvent.…”

mentioning

confidence: 99%

Synthetic application of methyl(phenylthio)ketene. Synthesis of vicinal-substituted cyclopentene derivatives

Ishida¹,

Minami²,

Agawa³

1979

J. Org. Chem.

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mol of phase-transfer catalyst. Solid Chloramine-T trihydrate (15.5 g, 0.0055 mol) was slowly added with stirring and cooling with a water bath. After addition was complete the water bath was removed; stirring was continued until the reaction was complete (usually 1-2 h) as ascertained by occasional monitoring by a thin-layer chromatography. The reaction mixture was washed with 200 mL of cold 5% aqueous sodium hydroxide followed by two washes with 200-mL portions of water. The dichloromethane layer was dried over anhydrous magnesium sulfate, filtered, and concentrated. The crude sulfilimine was recrystallized from methanol-water (9:l).General Procedure for Preparation of Oxiranes. The N -( p -tolylsulfony1)sulfilimine (3 mmol) was dissolved in 10 mL of dimethyl sulfoxide in a dry nitrogen atmosphere. After addition of 1 equiv of butyllithium in hexane the mixture was magnetically stirred for 10 min a t room temperature, and the aldehyde or ketone (3.0 mmol) was added with a syringe. The reaction mixture, after stirring a t ambient temperature for 18-20 h, was poured into 10% aqueous sodium chloride. The product was obtained by several extractions with hydrocarbon solvent, washing the combined extracts with water, drying over anhydrous sodium carbonate, and short-path distillation.Reaction of Chloramine-T with 3-Methyl-l-(phenylthio)-2-butene (4, R = Ph). Sulfide 4 (R = Ph), bp 120-122 "C (6 mm), prepared in 93% yield by alkylation of sodium benzenethiolate with l-bromo-3-methyl-2-butene in ethanol, was subjected to the general procedure given above for reaction of Chloramine-T with sulfides a t both ambient temperature and 0 "C. In each case an oil was obtained in 63 and 53% yield, respectively, which was identified as N-(l,ldimethyl-2-propenyl)-N-(pheny1thio)-p-toluenesulfonamide (6, R = Ph): 'H NMR (CDCl3) 6 1.5 (6, s), 2.3 (3, s) 4.8-6.3 (3, vinyl multiplet), 7-8 (9, Ar). Reaction of Chloramine-T with 3-Methyl-l-(methylthio)-2-butene (4, R = CHa). Sulfide 4 (R = CHa), bp 79-81 "C (77 mm), was treated with Chloramine-T according to the general procedure. The crude product was washed with ether to give the sulfilimine 5 (R = CH3) (40%): mp 73.5-75 "C; 'H NMR (CDC13) 6 1.68 and 1.72 (6, 2 s), 2.38 (3, s), 2.58 (3, s), 3.54 (2, d), 5.02 (1, t), 7-8 (4, AB quartet). These crystals were stored for several months in the refrigerator without noticeable deterioration. Evaporation of the ether extract and chromatography of the residue gave, asan oil, therearrangedproductN-(l,l-dimethyl-2-propenyl)-Ai-(methy1thio)-p-toluenesulfonamide (6,.R = CH3) (19%); 'H NMR (CDC13) 6 1.57 (6, s), 2.42 (6, s, ArMe and SMe), 4.9-6.4 (3, vinyl multiplet), 7-8 (4, AB quartet). Acknowledgment. This work was supported by a grant from the National Science Foundation. Registry No.-1 (R = Ph; R' = Me), 10330-22-0; 1 (R = Ph; R' = Ph), 13150-76-0; 1 (R = n-C&I13; R' = n-CsHls), 69745-50-2; 1 (R = Et, R' = CHzCHzOH), 69745-51-3; 1 (R = PhCH2, R' = -oxaspiro[2.5]octane, 185-70-6; cis-6-tert-butyl-l-oxaspiro[2.5]octane, 7787-78-2; trans-6-tert-bu...

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New synthetic reactions. New approach to geminal alkylation

Cited by 34 publications

References 2 publications

N-Nitromethylphthalimide. A formyl anion equivalent

N-Nitromethylphthalimide. A formyl anion equivalent

Carbonylation

Synthetic application of methyl(phenylthio)ketene. Synthesis of vicinal-substituted cyclopentene derivatives

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