Butyl chloroformate

Handling, Storage, and Precautions unstable at rt. t-Butyl chlo-roformate should be kept as a solution in anhydrous solvent at low temperature (deep freezer) and for a period of time not exceeding a few days. Decomposition leads to high pressure in the storage vessel. May contain some residual phosgene. Reacts with DMSO or DMF. 

Related Reagents. 7V-(r-Butoxycarbonyloxy)phthalimide N-(r-Butoxycarbonyloxy)succinimide t-Butyl Azidoformate t-Butyl Chloroformate Di-r-butyl Dicarbonate. 

Michael S. Wolfe National Institutes of Health, Bethesda, MD, USA 

Solubility sol ether, toluene, and most organic aprotic solvents. Form Supplied in not commercially available should be prepared from f-butanol or potassium r-butoxide and phosgene shortly before use. 

Reaction of pyridine compounds with Boc-Cl and Sodium Borohydride in methanol at —65 °C afforded the corresponding A -r-butyloxycarbonyldihydropyridine derivatives in good yield (eq 2).  

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PEROXIDES AND PEROXIDE COMPOUNDS - ORGANIC PEROXIDES] (Vol 18) n-Butyl chloroformate [592-34-7]... 

Chloroformates are shipped in nonretumable 208-L (55-gal) polyethylene dmms with carbon steel overpacks or high density polyethylene dmms. Eor bulk shipments, insulated stainless-steel tank containers and tmcks provide secure protection. Tank tmck and rail car quantities are shipped using equipment dedicated for these types of products. Materials such as isopropyl chloroformate, benzyl chloroformate, and j -butyl chloroformate that require refrigeration are precooled when shipped in bulk containers. Bulk shipments that are precooled must proceed to the destination without layover. Dmm shipments of IPCE, BCE, and SBCE must be shipped in refrigerated containers. Many of the chloroformates are only shipped in tmck load shipments. The U.S. Department of Transportation (DOT) Hazardous Materials Regulations control the shipments of chloroformates, as described in Table 3. 

XCH2C(CH3)20C0C1, THF, Et3N, H2O, CHCI3, 0°, 1.5 h (X = Br, 41-79% yield X = Cl, 60-86% yield). These halo-substituted r-butyl chloro-formates are more stable than an unsubstituted r-butyl chloroformate. 

Although the submitters report that this crude product is suitable for use in the next step of this preparation, the checkers found that once when using the crude product the subsequent reaction did not go to completion unless an extra quantity of the diamine base was added. This suggests that some potentially acidic impurity such as crude product and could interfere with the subsequent reaction. The checkers therefore recommend that the product be purified before use in the next step of this preparation,... 

In 2004, Alterman et al. apphed their cyanation protocol to the synthesis of N-(t-butyl)-3-(4-cyanobenzyl)-5-isobutylthiophene-2-sulfonamide [61]. Deprotection of the sulfonamide followed by carbamate formation via reaction with butyl chloroformate finally gave the target compoimd for biological evaluation as a selective angiotensin 11 AT2 receptor agonist (Scheme 65). The cyano derivative, however, showed only a low affinity for the AT2 receptor (Ki value >10 p,M). 

C22H22C1N,0 114772-55-3) see Losartan potassium tert-butyl chloroformate (C5H9CIO2 24608-52-4) see Cefalexin 2-butyl-4-chloro-5-hydroxymethyiimidazole (CSII13CIN2O 79047-41-9) see Losartan potassium 2-butyl-4-cbloro-lif-imidazole-5-carboxaldehyde (CnHiiClNjO 83857-96-9) see Eprosartan Losartan potassium... 

Butanetriol trinitrate tert-Butoxycarbonyl azide n-Butyl chloroformate... 

FIGURE 3.17 Reagents for protection of amino groups as the ferf-butoxycarbonyl derivatives. terf-Butyl chloroformate is rarely used because of its low boiling point. The oxime is 2-ferf-butoxycarbonyloximino-2-phenylacetonitrile,45 Boc20 = di-ferf-butyl dicarbonate, or di-terf-butyl pyrocarbonate.46 (Tarbell et al., 1972 Pozdvev, 1974). Acylations are carried out at pH 9 to avoid dimerization. 

In contrast to this demonstration of bimolecularity, Hall and Lueck82 showed the possibility of acylium ion formation from benzoyl chloride by its reaction with mercuric perchlorate. In common with dimethylcarbamyl chloride, dimethylsulphamyl and tetramethyldiamidophosphochloridate, benzoyl chloride reacted readily to form the corresponding acylium ion /i-butyl chloroformate however was inert. Kivinen138 studied the effect of mercuric chloride on the ethanolysis of 4-methoxybenzoyl chloride, benzoyl chloride and 4-nitrobenzoyl chloride and obtained the following approximate relative rates for the effect of mercuric chloride (0.30 M) in ethanol, 4-MeO, 2.91 4-H, 1.00 4-NOz, 1.03, confirming the SN2 character of the 4-nitro-... 

Fused l,2,5-triazepine-3,6-diones 88-90 were synthesized from (2 S )-proline methyl ester 205 by treating the latter with bromoacetic acid 206 in the presence of tiro-butyl chloroformate 207 (Scheme 46). The resultant bromoacetamide 208 on further treatment with hydrazine hydrate in EtOH gave 88-90 via cyclization through displacement of bromine <1996CC85>. 

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