Sequential three-step process

A sequential three-step process consisting of diaryl ether Hthiation, bor-ylation, and hydrolysis transforms dibenzofurans into dibenzoxaborininols 11 (Scheme 5) (2013MI3625)... 

In order to make useful products from polymers we typically follow a three-step process in which we sequentially melt, shape, and cool the polymer. Naturally, given the wide variety of polymers available and their myriad applications, variations on this general process abound. In this chapter, we will concentrate on extrusion, some variant of which is used in the majority of commercial fabrication processes. 

The Pandey group has developed a silver fluoride-promoted desily lation of tertiary bis(silyl)amines as an interesting alternative method to access azomethine ylides (Scheme 2.10).18 Notably, this method allows the generation of nonstabilized azomethine ylides under essentially neutral conditions. The starting materials are prepared by a three-step process, sometimes coupled into a single operation. For example, Boc-protected pyrrolidine 36 can be sequentially deprotonated and silylated twice in a one-pot reaction (Scheme 2.10). Removal of the Boc group and alkylation of the free amine leads to bis(silyl)amine 37. When this compound is treated with 2 equiv of silver fluoride in the presence of phenyl vinyl sulfone, rapid formation of products 39 as single stereoisomers results. 

A nice extension of this chemistry to sequential anionic/radical/anionic sequence was also provided [5, 9]. Normally after acyl addition and radical cyclization onto a C = C bond, the newly formed carbon radical is reduced to an organosamarium intermediate which is subsequently protonated. However, as depicted in Scheme 5, this organosamarium may be trapped in the presence of a ketone substrate, thus terminating this three-step process. In another demonstration of how such anions may be further exploited, substrates possessing vinyl ethers as the radical acceptor were found to under-... 

Inducing the transition to a d-ASC is a three-step process, based on two psychological (and/or physiological) operations. The process is what happens internally the operations are the particular things you do to yourself, or someone does to you, to make the induction process happen. In the following pages the steps of the process are described sequentially and the operations are described sequentially, but note that the same action may function as both kinds of induction operation simultaneously. 

Note that the case for emission of a blue photon by Tm3+ is slightly different than that of Er ". A three-step process is indicated. This may consist of excitation of the Tm3+ ion and energy transfer from two excited Yb3+ ions, or excitation of the Tm3+ ion by exchange (sequential excitation) with three excited Yb3+ sites. Note that two relaxation steps (phonon emission to the host lattice) would be Involved. 

An ABC triblock terpolymer was successfully synthesized by a sequential three-step RAFT polymerization process of N-n-propylacrylamide, N-isopropylacrylamide and N,N-ethylmethylacrylamide monomers [41], The different cloud points of the respective blocks, present in the terpolymer, are responsible for the rich temperature depended solution self-assembly of the sample in aqueous media. 

Grela and coworkers attached (4b) to butyl diethyl silyl polystyrene to yield catalyst (289) in three steps. The catalyst had good activity toward formation of trisubstituted aUcene products in RCM and CM processes. The catalysts retained efficacy for up to 6 cycles and could be used sequentially on different substrates without cross contamination. 

The initial shock wave from the detonation of explosives increases the pressure in the inner vessel to up to thousands of atmospheres (10 gigapascals) in 0.3 milliseconds. As illustrated in Figure 4-2, agent is destroyed as a result of a three-sequential-step process ... 

Block Copolymer Synthesis by Two-Step Sequential Monomer Addition and Coupling In order to avoid the problems associated with the three-step sequential monomer addition process, a two-step sequential monomer addition process followed by addition of a difunctional... 

Treatment with excess trifluoroacetic acid furnished the (dihydroiminoethano) carbazole 107 in 71% overall yield. Epoxidation of the alkene followed by a two-step protecting group modification gave epoxide 108, which underwent an oxidative epoxide opening followed by silyl protection to give silyl ether 109. Alloc deprotection, alkylation with (Z)-2-iodo-2-butenyl tosylate, followed by an intramolecular Heck reaction delivered pentacyclic diamine 110. A three-step formation of the p-ketoester 111 followed by a three-step reduction process afforded ester 112, which underwent a reduction and deprotection sequence to provide minfien-sine (99). A sequential catalytic asymmetric Heck-(V-acyliminium ion cyclization for the delivery of the enantiopure 3,4-dihydro-9a,4a-(iminoethano)-9//-carbazole is the highlight of the synthesis. 

The three steps associated with electrochemical reactions, i.e., transport of reactant(s) to the interface, the electron transfer (surface) reaction and transport of product(s) from the interface, are sequential. Therefore, the overall rate of reaction is controlled by the slowest of the three steps. When the transport processes are capable of operating at high rates relative to the electron transfer reaction, the rate of the overall reaction can be described by equations of electrodekinetics. These types of electrode reactions are said to be "under activation control". 

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