Isopropyl carbonate

Following the initial work by Smart et al., similar efforts were reported based on various binary and ternary compositions, such as EC/DMC/EMC (1 1 1) 503,505,509 eC/DMC/DEC (2 2 l),so5 EC/EMC (1 3), ° EC/DMC/methylpropyl carbonate (MFC) and EC/DMC/isopropyl carbonate (iPC) at a series of varying compositions.Unfortunately, below —30 °C the above compositions still failed to function well. ... 

Suitable inert solvents include methyl ethyl ketone, benzene, ethylbenzene and toluene. Suitable initiators include peresters and peroxycarbonates such as ferf-butyl perbenzoate, ferf-butyl peroxy isopropyl carbonate, fcrf-butyl peroctoate, tert-butyl peroxy isonon-... 

Near-quantitative yields of aryl isopropyl carbonates were realized in a similar process when diisopropyl peroxydicarbonate was reacted with alkyl-substituted aromatics.794 Substitution is effected by a radical entity possessing a considerable ionic character. 

The reaction of thiophene and its derivatives with diisopropyl peroxydicarbonate has been investigated (74JOC504). In the presence of CuCl2 as oxidant, 2-thienyl isopropyl carbonate is formed in 70% yield (Scheme 62). In the absence of added oxidant, loss of a hydrogen atom from the a-complex radical is less efficient. 

Addition time, 1.5 hrs. hold time, 1.5 hrs. size of batch, 1 liter. c Legend DCP, dicumyl peroxide. DTBP, di-ferJ-butyl peroxide. BzP, benzoyl peroxide. BPIC, butyl peroxy isopropyl carbonate. AZBN, azobisisobutyronitrile. 

Equation 1 is a homodesmotic reaction having the same numbers and types of structural units on both sides of the equation. Note that the cyclopropyl position (2° carbon) is modelled by the isopropyl carbon (also 2°). It is worth noting briefly that... 

Diisopropyl peroxydicarbonate, [(CH3)2CHOCOO]2 is a rather exotic reagent with limited availability and use. The treatment of toluene with diisopropyl peroxydicarbonate yields a mixture of all three tolyl isopropyl carbonates [232]. 

Besides Ampicillin, 1-chloroalkyl alkyl carbonates and particularly 1-chloroethyl ethyl carbonate (CEEC), 1-chlo-roethyl isopropyl carbonate (CEIC), 1-chloroethyl cyclohexyl carbonate (CECC) and chloromethyl ethyl carbonate (CEMC), have been proposed to modify numerous compounds. Among the many types of prodrugs patented which require this method, there are examples of ... 

Alkenyl carbonates readily add HBrtogive 1-bromoal-kyl carbonates which are better alkylating agents for the modification of carboxylic acid functions than 1-chloroalkyl carbonates as already mentioned in section 3-2-2-3 (Ref. 85). For example, 1-bromoethyl tisopropyl carbo nate (BEIC) was prepared at pilot scale in 92 % distilled yield by bubbling HBr through vinyl isopropyl carbonate, neat, at 20-25°C as depicted in scheme 110. 

Scheme 110 Preparation of I bromoethyl isopropyl carbonate (BEIC).

In the presence of cupric chloride, toluene is converted by the reagent into tolyl isopropyl carbonates, the ortho isomer predominating. ... 

Ephedrine and pseudoephedrine are structurally mirror images of each other. This is possible because they have a chiral center, the isopropyl carbon to which the nitrogen atom is attached. If the reduction is done in such a manner that the chiral nature of the substance is not jumbled (i.e. racemization), then ephedrine and pseudoephedrine give rise to "1" and "d" methamphetamine, respectively. The "1" form is several times more potent than the "d" form. Meth produced from phenylacetone is a racemic mixture, meaning that it is a 50-50 mix of the "1" and "d" forms of meth. Obviously, a batch of pure "1" form is most desirable, a racemic mixture is OK, and pure... 

Dinobuton. Carbonic acid 1 -rnethylclhyt 2-(I-meihylpropyl)-4,6-dlnitrophenyt ester carbonic acid 2-sec-butyl-4.ft-iliniirophrnyl isopropyl ester 2-see-butyl 4,6-dini-trophenyi isopropyl carbonate dinitro-sec-butylphenyl isopropyl carbonate isopropyl 2,4-dinitro-6-see-butylpheny] carbonate Acrex Desstn Sytasol. C..HuN-0, mol wt 326.30. C 51.53%, H 5.56%, N 8.59%, O 34.32%. Prepn Pianka, Pol ton, U,S. pats. 3,234,082 3,234,260 (both 1966 to Murphy Chem.). Metabolism studies Bandal, Casida, J. Agr. Food Chem. 20, 1235 (1972). 

Methyl, ethyl, and isopropyl carbonates with pronounced in vitro activity were further evaluated for in vivo antimalarial potency. Both the methyl and ethyl carbonates significantly increased the mice s life span as compared with 3,15-di-O-accetylbruceolide (230) and chloroquine (225) [121],... 

Noie how ihe isopropyl group has priority over n-propyl At the first point of difference (arrows), the isopropyl carbon is connected to C.C.H whereas the /i-propyl carbon is connected to C,H,H. The boldface atoms (second C for isopropyl vs. first H for n-propyl) set the priority. 

D. Clerin, A. Lacroix, and J.-P. Fleury, Tetrahedron Letters, 2899 (1976). l henyl-[2-(p-phenyIazophenyl)isopropyl]carbonate (AZOC—OPh),... 

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