Observations on the synthesis of functionalised methyleneaziridines

Ince, Julie; Ross, Tracy; Shipman, Michael; Slawin, Alexandra M. Z.; Ennis, David S.

doi:10.1016/0040-4020(96)00308-0

Cited by 35 publications

(26 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 2,2‐dichloroacyl chlorides (apart from dichloroacetyl chloride and trichloroacetyl chloride, which were purchased) were prepared, on our mini‐pilot plant, by chlorination of acyl chlorides with Cl 2 in the presence of tetrabutylammonium chloride 31. The starting amides 1 – 8 and 10‐ ‐ 12 were obtained through standard aminodechlorination of acyl chlorides with allylic amines (all prepared by N ‐alkylation of amines, adapting Shipman’s method32). The sulphonamide 9 was assembled by acylation of the lithium salt of N ‐allylmethanesulphonamide 19a.…”

Section: Methodsmentioning

confidence: 99%

Efficient and Green Route to γ‐Lactams by Copper‐Catalysed Reversed Atom Transfer Radical Cyclisation of α‐Polychloro‐N‐allylamides, using a Low Load of Metal (0.5 mol%)

et al. 2013

View full text Add to dashboard Cite

The cyclisation of N-allyl-N-substituteda-\ud polychloroamides is efficiently obtained through\ud a copper-catalysed activators regenerated by electron\ud transfer–atom transfer radical cyclisation process,\ud with a metal load of only 0.5 mol%. The redox\ud catalyst is introduced in its inactive form as copper(\ud II) chloride/[nitrogen ligand] complex, and continuously\ud regenerated to the active copper(I) chloride/[\ud nitrogen ligand] species by ascorbic acid. To\ud preserve the catalyst integrity, the hydrochloric\ud acid, released after each regeneration cycle, has\ud been quenched by carbonate. The choice of the solvent\ud is critical, the best performance being observed\ud in ethyl acetate-ethanol (3:1)

show abstract

Section: Methodsmentioning

confidence: 99%

Efficient and Green Route to γ‐Lactams by Copper‐Catalysed Reversed Atom Transfer Radical Cyclisation of α‐Polychloro‐N‐allylamides, using a Low Load of Metal (0.5 mol%)

et al. 2013

View full text Add to dashboard Cite

show abstract

“…Dichloroacetyl chloride was purchased, whereas 2,2‐dichloropropanoyl chloride was prepared, in our mini‐pilot plant, by chlorination of propanoyl chloride with Cl 2 in the presence of tetrabutylammonium chloride 26. The starting amides 1a , 2a and 4a were obtained through the standard aminodechlorination of acyl chlorides with allylic amines (all prepared by N ‐alkylation of amines, adapting the Shipman’s method27). The sulfonamide 3a was instead prepared by acylation of the lithium salt of N ‐allylmethanesulfonamide 5a.…”

Section: Methodsmentioning

confidence: 99%

Electrochemical Approach to Copper‐Catalyzed Reversed Atom Transfer Radical Cyclization

et al. 2015

View full text Add to dashboard Cite

Electrochemically mediated atom transfer radical cyclization (eATRC) has been developed as an easy and clean method allowing the synthesis of halogenated cyclic compounds. This method has been successfully applied to the copper-catalyzed atom transfer radical cyclization of some N-allyl-alpha,alpha-dichloroamides in acetonitrile (CH3CN) using a copper complex with tris(2-pyridylmethyl)amine (TPMA) with a metal loading of 1%. The catalyst is introduced as [Cu(II)TPMA](2+) and is activated and continuously regenerated to its active copper(I) form by reduction at a platinum (Pt) electrode. During the ATRC process a new copper(II) complex, namely, [ClCu(II)TPMA](+), whose reduction potential is ca. 0.350 V more negative than that of the starting [Cu(II)TPMA](2+), is formed. Therefore, the choice of the applied potential is critical and should be done taking care that all copper(II) species are reduced to copper(I). The compounds undergo very high conversions (79-100%) in a few hours of electrolysis, producing a cyclic gamma-lactam (yield 60-98%) as a mixture of two isomers, with a good cis-diastereoselectivity [dr (cis/trans) = 59/41-83/17]. [Cu(II)PMDE-TA](2+) (PMDETA= N, N, N',N '',N ''-pentamethyldiethylenetriamine) which is much cheaper, albeit less reactive than [Cu(II)TPMA](2+), was also investigated but the results were not satisfactory

show abstract

“…Removal of the solvent under reduced pressure and subsequent column chromatography (2% methanol-DCM using silica pre-treated with triethylamine) gave 6 (1.10 g, 72%) as a light orange oil. ν max (film)/cm Ϫ1 3300, 2947, 1627, 1457, 1296; δ H (300 MHz, CDCl 3 ) 5.70 (1H, s, ᎐ ᎐ CH), 5.56 (1H, s, ᎐ ᎐ CH), 4.32 (1H, t, J 5.4, CH), 3.46 (2H, s, NCH 2 C(Br)᎐ ᎐ ), 3 Br requires 252.0599).…”

Section: N-(2-bromoprop-2-enyl)-44-dimethoxybutylaminementioning

confidence: 99%

Observations on the ring opening reactions of 2-methyleneaziridines with acid chlorides and alkyl chloroformates

Ennis

Ince

Rahman

et al. 2000

J. Chem. Soc., Perkin Trans. 1

Self Cite

View full text Add to dashboard Cite

A variety of 1-alkyl-2-methyleneaziridines react with alkyl chloroformates (MeO 2 CCl, PhCH 2 O 2 CCl) or acid chlorides (AcCl, p-NO 2 C 6 H 4 COCl) at room temperature in nonpolar solvents (CH 2 Cl 2 , THF, toluene) to produce ring opened enamide products in moderate to good yields. Mechanistic studies using 3-deuterio-N-(1-phenylethyl)-2-methyleneaziridine suggest the reactions proceed by initial N-acylation to form the corresponding aziridinium cation (e.g. 27) which subsequently undergoes regiospecific ring opening by chloride ion at the sp 3 hybridised aziridine carbon atom to produce the observed products.

show abstract

Observations on the synthesis of functionalised methyleneaziridines

Cited by 35 publications

References 14 publications

Efficient and Green Route to γ‐Lactams by Copper‐Catalysed Reversed Atom Transfer Radical Cyclisation of α‐Polychloro‐N‐allylamides, using a Low Load of Metal (0.5 mol%)

Efficient and Green Route to γ‐Lactams by Copper‐Catalysed Reversed Atom Transfer Radical Cyclisation of α‐Polychloro‐N‐allylamides, using a Low Load of Metal (0.5 mol%)

Electrochemical Approach to Copper‐Catalyzed Reversed Atom Transfer Radical Cyclization

Observations on the ring opening reactions of 2-methyleneaziridines with acid chlorides and alkyl chloroformates

Contact Info

Product

Resources

About