1- chloroethyl chloroformate

Cm.OROCARBONSANDCm.OROHYDROCARBONS - BENZYL CbD ORIDE, BENZAL CbD ORIDE AND BENZOTRICm ORIDE] (Vol 6) 2-Chloroethyl chloroformate [627-11-2]... 

Deall lation. Chloroformates such as vinyl chloroformates (40) are used to dealkylate tertiary amines. Chloroformates are superior to the typical Von Braun reagent, cyanogen bromide, because of increased selectivity producing cleaner products. Other chloroformates such as aHyl, methyl, phenyl, and trichloroethyl have also been used in dealkylation reactions. Although the dealkylation reaction using chloroformates is mostiy carried out on tertiary amines, dealkylation of oxygen or sulfur centers, ie, ethers or thioethers, can also be achieved. a-Chloroethyl chloroformate [50893-53-3] (ACE-Cl) (41,42) is superior to all previously used chloroformates for the dealkylation reaction. ACE-Cl has the advantage that the conditions requked for ACE... 

Treatment of perhydropyrido[2,l-c][l,4]oxazin-l-ones 236 with vinyl and 1 -chloroethyl chloroformate in the presence of 4A molecular sieves afforded ring-opened (2i )-pipecolic acid derivatives 237 (97SL799, 98EJOC2461, 98T10309). Similarly, perhydropyrido[l,2-c][l,4]oxazin-l-one 238 yielded (2S)-pipecolic acid derivative 239 (98T10309). 

Tertiary aliphatic amines are also cleaved by HI, but useful products are seldom obtained. Tertiary amines can be cleaved by reaction with phenyl chloroformate R3N -h ClCOOPh —> RCl 4- R2NCOOPh. a-Chloroethyl chloroformate behaves similarly.Alkyl halides may be formed when quaternary ammonium salts are heated R4N+X" R3N -)- RX. ... 

Treatment of perhydropyrido[2,T2][l>4]oxazin-l-ones 259 with vinyl and 1-chloroethyl chloroformate afforded ring-opened (2A)-pipecolic acid derivatives 260 (Equation 49) <1997SL799, 1998EJ02461, 1998T10309>. Similarly, perhydropyrido[l,2-f][l,4]oxazin-l-one 261 yielded (26 )-pipecolic acid derivative 262 (Equation 50) <1998T10309>. 

Carbachol Carbachol, 2-carbamoyloxy-iV,iV,iV-trimethylethyl ammonium chloride (13.1.7), is made by reacting 2-chloroethanol with phosgene, which forms 2-chloroethyl chloroformate (13.1.5). Upon reaction with ammonia, it turns into the corresponding amide (13.1.6), which is further reacted with an equimolar quantity of trimethylamine, giving carbachol (13.1.7) [9-13],... 

A,r-Benzyl groups can be removed by reaction of amines with chloroformates. This can be a useful method for protecting-group manipulation if the resulting carbamate is also easily cleaved. A particularly effective reagent is a-chloroethyl chloroformate, which can be removed by subsequent solvolysis.78... 

The general synthesis of the Daniphos ligands starting from enantiomerically pure [(R)-l-(phenylethyl)dimethylamine]chromiumtricarbonyl 1, is depicted in Scheme 1.4.1 [15]. A directed ortho-metallation (DOM) and subsequent quench with a chlorophosphine leads to an enantiomerically pure planar-chiral complex, which after chlorination using ACE chloride (1-chloroethyl chloroformate) is transformed into the desired diphosphine by a nucleophilic substitution without any loss of optical purity (Scheme 1.4.1) [6, 10]. 

Another approach to the lycorane skeleton involving an intramolecular Diels-Alder reaction commenced with the conversion of the unsaturated nitrile 138 to the imine 139 by sequential reduction with diisobutylaluminum hydride followed by condensation with but-3-enylamine (Scheme 13) (118). When 139 was acy-lated with chloroethyl chloroformate in the presence of Hiinig base and the resulting dienamide heated at 140°C, the bicyclic carbamate 141 was isolated. If it is assumed that the Diels-Alder reaction proceeded via an exo transition state,... 

Dimethylaminopyridine 1-Chloroethyl chloroformate (Chloromethyl)cyclopropane 3-Chloroperbenzoic acid Boron tribromide... 

A solution of 6-acetylcodeine (10.0 g, 29.3 mmol), 1-chloroethyl chloroformate (5.51 g, 37.8 mmol), and proton sponge (1.0 g) in methylene chloride (80 ml) was heated at reflux for 80 min. The reaction mixture was evaporated in vacuo to dryness. The residue was chromatographed on silica gel with ethyl acetate to give 6-acetyl-17-(l-chloroethoxycarbonyl)norcodeine as an oil (12.13 g), which was dissolved in methanol with a few drops of cone. HCI. The solution was heated at reflux for 1 hr and evaporated in vacuo to almost dryness. The residue was added hexane and filtered to give 6-acetylnorcodeine hydrochloride (10.7 g, 100% yield). 

Tartaric acid, L-Lithium bromide N-Phenylsulfonyl indole 1,2-Dibromoethane Trifluoroacetic acid 1-Chloroethyl chloroformate Formaldehyde Allyl bromide... 

Monocyclic 1,2,3-triazines react with ketene silyl acetal, or silyl enol ether, in the presence of 1-chloroethyl chloroformate to give 5-(substituted)-2-(l-chloroethoxycarbonyl)-2,5-dihydrotriazines which are readily oxidised, and hydrolysed, with ceric ammonium nitrate in aqueous acetonitrile to 5-(substituted)-triazines (Scheme 24) [95CPB881],... 

JAP(K)242587], The latter compounds were also obtained directly from carboxamides 31 by reaction with 2-chloroethyl chloroformate followed by treatment with ethanolic potassium hydroxide (89H985). 

S, 4S) Methyl-4-(4-chlorophenyl)-l-methylpiperidine-3-carboxylate (33 mmol) and 5.4 ml chloroethyl chloroformate were dissolved in 30ml CH2Cl2 refluxed 3 hours, cooled, and 40 ml IM HCl added. The mixture was filtered through silica gel and purified using column chromatography on silica with EtOAc/ETA, 9 1, and the product isolated in 78% yield as a clear oil. H-NMR data supplied. 

DEALKYLATION OF AMINES f-Butyldi-methylsilyl triflouromethanesulfonate. 2-Chloroethyl chloroformate. 

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