Furukawa procedure

The possibility of a radical mechanism is supported by the observation of the accelerating effect of molecular oxygen on the cyclopropanation. Miyano et al. discovered that the addition of dioxygen accelerated the formation of the zinc carbenoid in the Furukawa procedure [24a, b]. The rate of this process was monitored by changes in the concentration of ethyl iodide, the by-product of reagent formation. Comparison of the reaction rate in the presence of oxygen with that in the... 

An alternative procedure consisted of trichloroacetylation of the end groups and redox initiation with sulfur dioxide and pyridine309. In these two methods the block efficiency was not high. An improved method was proposed by Furukawa in which a macromolecular initiator is prepared from polyetherglycol and azobiscyanovaleroyl dichloride310 311. ... 

A number of modifications of the original Simmons-Smith cyclopropanation procedure have been reported. Furukawa s reagent, (iodomethyl)zinc derived from diethylzinc and diiodomethane, ° or its modification using chloroiodomethane instead of diiodomethane, ° allows more flexibility in the choice of solvent. The reagent is homogeneous and the cyclopropanation of olefins can be carried out in non-complexing solvents, such as dichloromethane or 1,2-dichloroethane, which greatly increase the reactivity of the zinc carbenoids. 

A paper of Furukawa and Nitta is cited first to imderstand the NEMD simulation semiquantitatively, since, even though the paper deals with various pore shapes, complicated simulation procedure is described clearly. 

Furukawa and coworkers [81-83] have developed procedures for preparing alternating copolymers of butadiene with propylene and other 1-olefins. The structures of these polymers have been studied by 220 MHz pmr [84] and 25 MHz cmr spectroscopy [85]. 

T. Asayama, Y. Abe, N. Miyaji, M. Koi, T. Furukawa, E. Yoshida, Evaluation procedures for irradiation effects and sodium environmental effects for the structural design of Japanese fast breeder reactors, ASME J. Pressure Vessel Technol. 123 (2001) 49. 

Furukawa and coworkers realized the first enantioselective substoichiometric epoxidation reaction of aldehydes via the sulfide alkylation/deprotonation route, based on their one-pot procedure for the synthesis of oxiranes using sulfides directly rather than the preformed sulfonium salts [6]. In the presence of 50 mol% sulfide 1, which was prepared in three steps starting from (-l-)-camphorsulfonic acid, a 50% yield and 47% ee were obtained in the reaction of benzaldehyde with benzyl bromide under solid-liquid two-phase conditions (solid KOH/CH3CN). A catalyst turnover (TON = 2.3) was also observed when 10mol% catalyst was used in the reaction of 4-chlorobenzaldehyde (Scheme 20.3). The O-methylated derivative of sulfide 1 gave the trans epoxides with an opposite configuration. 

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