Superbasicity

The technique of neutralization and the production of superbase systems from synthetic sulfonates are similar to those employed for the natural sulfonates. 

The "zip-reaction (U. Kramer, 1978, 1979) leads to giant macrocycles. Potassium 3- ami-nopropyl)amide = KAPA ( superbase ) in 1,3-diaminopropane is used to deprotonate amines. The amide anions are highly nucleophilic and may, for example, be used to transam-idate carboxylic amides. If N- 39-atnino-4,8,12,16,20,24,28,32,36-nonaazanonatriacontyl)do-decanolactam is treated with KAPA, the amino groups may be deprotonated and react with the macrocyclic lactam. The most probable reaction is the intramolecular formation of the six-membered ring intermediate indicated below. This intermediate opens spontaneously to produce the azalactam with seventeen atoms in the cycle. This reaction is repeated nine times in the presence of excess KAPA, and the 53-membered macrocycle is formed in reasonable yield. 

Superbase mix of rice maltodextrin, starch xanthan, and whey protein Excel... 

Carbanions of substituted diacetylenes 68 generated under the action of complex superbase -BuLi/t-BuOK/THF/hexane add to carbon disulfide to afford the intermediates 69 which further transform to thieno[2,3-i]thiophenes (70) (90DIS 91SC145). 

Basic compound To neutralise strong mineral acids (from fuels) Barium or basic calcium salts of sulphonic acids and alkylsalicylic acid. Superbasic and hyperbasic additives are basic salts with a large excess of base... 

P4-/-Bu = superbase phosphazene [3-(/ v/-butylimino)-1,l,l,5,5.5-hcxakis(dimethylamino)-3-[[tris(dinicthy]amiiio)phosphorany]ideneJamino -l 3/.5, 525-1,4-triphosphazadiene]. 

Proc. 13th Intern. Conf. Catal. ( New Trends in Solid Superacids and Superbases ,... 

Highly basic systems such as KOH/DMSO (superbasic Trofimov conditions [291]) have been used for the N-vinylation of 3-vinylpyrrole (Eq. 4.75) [292]. 

These conditions are also applicable to functionalized systems that are compatible with metallation by this superbase. 69... 

This result has been further substantiated by the work of Koppel et al. <2001PCA9575>. They conducted a theoretical study of the basicity of phosphorus imines and ylides. Verkade bases 6-8 were included. They showed basicities comparable to commercially used organic superbases (/-BUP4 phosphazene imine), with compound 8 in particular giving calculated basicities similar to Li3P and Li20. 

In a deliberate attempt to trap the carbanion/amide intermediates formed en route to the homoamido inverse crown complexes, [ (TMP)(/z-Bu)(/x-TMP)NaMg(TMEDA) ] 432 (Figure 38) was isolated and characterized.440 This complex spans the superbase and inverse crown structural modalities. 

Trofimov has extended his previously reported heterocyclization of ketoximes 39 with acetylene to propyne or its isomer allene in superbase systems (MOR/DMSO M = K, Cs, R = H, t-Bu) to afford a facile synthesis of substituted pyrroles 40 and 41 . Due to a fast propyne to allene protropic isomerization under the reaction conditions, the product is the same regardless of which species is employed. 

Gusarova, N.K., Shaikhudinova, S.I., Dmitriev, V.I., Malysheva, S.F., Arbuzova, S.N., and Trofimov, B.A., Reaction of red phosphorus with electrophiles in superbasic systems. VII. Phospholanes and phosphorinanes from red phosphorus and a,co-dihaloalkanes in a single preparative step, Zhur. Obshch. Khim., 65, 1096, 1995. 

To solve this first reduced problem, follow the steps of the descent algorithm outlined at the start of this section with some straightforward modifications that account for the bounds on x and y. When a nonbasic variable is at a bound, we must decide whether it should be allowed to leave the bound or be forced to remain at that bound for the next iteration. Those nonbasic variables that will not be kept at their bounds are called superbasic variables [this term was coined by Murtaugh and Saunders (1982)]. In step 1 the reduced gradient off(x,y) is... 

The variable y becomes superbasic. Because s is at its lower bound of zero, consider whether s should be allowed to leave its bound, that is, be a superbasic variable. Because its reduced gradient term is , increasing s (which is the only feasible change for s) increases the objective value. Because we are minimizing F, fix s at zero this corresponds to staying on the line x = y. The search direction d = and new values for y are generated from... 

First, the first element in the reduced gradient with respect to the superbasic variable y is zero. Second, because the reduced gradient (the derivative with respect to s) is 1, increasing s (the only feasible change to s) causes an increase in the objective value. These are the two necessary conditions for optimality for this reduced problem and the algorithm terminates at (1.5, 1.5) with an objective value of 2.0. 

Iteration number Objective Number function binding Number superbasics Norm of Number reduced infeasible gradient Hessian condition... 

As can be seen in the output shown in the box, at the starting point (iteration 0) there are two infeasible constraints, two superbasics, and sinf = 1. Using the usual formula, (x, y) for the first line search is calculated as follows ... 

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