N addition

Unusual cyclocarbonylation of allylic acetates proceeds in the presence of acetic anhydride and an amine to afford acetates of phenol derivatives. The cinnamyl acetate derivative 408 undergoes carbonylation and Friedel-Crafts-type cyclization to form the a-naphthyl acetate 410 under severe condi-tions[263,264]. The reaction proceeds at 140-170 under 50-70 atm of CO in the presence of acetic anhydride and Et N. Addition of acetic anhydride is essential for the cyclization. The key step seems to be the Friedel-Crafts-type cyclization of an acylpalladium complex as shown by 409. When MeOH is added instead of acetic anhydride, /3,7-unsaturated esters such as 388 are... 

E. Termine and K. G. Taylor, "A New Intumescent Flame Retardant Additive for Thermoplastics and Thermosets," n Additive Approaches to PolymerModification, SPE RETEC Conference Papers, Toronto, Ontario, Canada, Sept. 1989. 

Anlagenmgs-erzeugnis, n. addition product, -reaktion, /. addition reaction, -verbindung, /. addition compound. 

Zusatz-. additional, supplementary, auxiliary admixed, added additive, -element, n. (Metal.) alloying element, -feld, n, addi tional field, supplementary field, -gerat, n. Supplementary apparatus, attachment, -glied, n. additional term, supplementary term, -lack, m. blending varnish, zusatzlich, a. additional additive supplementary, auxiliary. 

Lemma 2 The lengths of all cycles in any size N additive CA over Tp must divide the length of the cycle obtained with an initial configuration containing a single nonzero site. 

The metal carbonyls Ni(CO)4, Fe(CO)s, and Cr(CO)6 are observed to be diamagnetic. This follows from the theoretical discussion if it is assumed that an electron-pair bond is formed with each carbonyl for the nine eigenfunctions available (3d64s4p3) are completely filled by the n bonds and 2(9 — n) additional electrons attached to the metal atom (n = 4, 5, 6). The theory also explains the observed composition of these unusual sub-... 

Aminoimidazole (64) has been reported to react with various bifunctional reagents to give bicyclic systems (Scheme 6). In some cases the initial N-addition-elimination product has been isolated (e.g., 68 and 69). 

The modes of reaction of several 5-aminoimidazoles (96) with the reagents (135-142) are summarized in Table V. The variation of product structure with reagent is clearly discemable. The preference for C- or N-addition has been interpreted in terms of a frontier orbital analysis of the reactants [92JCS(P1)2779, 92JCS(P1)2789] (see Section VI,C). The... 

Augustijn-Beckers, P. W. M., Hornsby, A. G., Wauchope, R. D. (1994) The SCS/ARS/CES pesticide properties database for environmental decision making, n. Additional compounds. Rev. Environ. Contam. Toxicol. 137, 1-82. 

Nephrotoxins (N) orototoxins (0) (eg., amphotericin B (N), cisplatin (N/0), cyclosporine (N), furosemide (0), NSAIDs (N), radio contrast (N), vancomycin (N) Additive adverse effects Monitor aminoglycoside SDC and renal function... 

The application of n additional thermodynamic potentials (of electric, magnetic or other origin) implies that the Gibbs phase rule must be rewritten to take these new potentials into account ... 

Fig. 6.2 (a) Niche dimension of a habitat that is co-limited by nitrogen (N), phosphorus (P), and potassium (K), and (b) niche dimension of the same habitat after N addition. The different shapes indicate soil areas that are limited by N, P, or K. If one nutrient is added, e.g., N by N deposition, the total soil area with limiting amounts of one or more nutrients for plant growth becomes smaller. The habitat becomes more uniform and may offer less niches for plants to coexist... 

RfLl phases The existence of these phases (cubic AuCu3 type) had been reported for R = La, Ce, Pr, Nd and Sm. Subsequently, however, Buschow and van Vucht (1967) found that many of the R3A1 phases do not form, unless some carbon is present. C atoms occupy the body-centred site, which in the AuCu3 type structure is normally vacant, while the Au atoms occupy the corners, and the Cu atoms the face-centred positions. When the face-centred position is completely filled, the structure is known as the anti-perovskite structure. This occurs for R = Nd, Sm, Gd, Tb, Dy Ho and Er. They also noted that neither N nor O would stabilize these compounds. Notice that Ce3Al and Pr3Al are truly binary compounds and C is not required for these two phases to form. Independently, Nowotny (1968) found that the anti-perovskite structure could be formed by C and N additions to R3M alloys, where M = Al, Ga, In, Tl, Sn and Pb. 

In this chapter, nucleophilic l,n-additions (n = 4, 6, 8,. ..) to acceptor-substituted dienes, enynes and polyenes are presented2. Addition reactions which obviously proceed via non-nucleophilic pathways (e.g. catalytic reductions, electrophilic or radical additions3), as well as 1,2-additions to the acceptor group, are not covered. 

I n addition to the direct oxidation of simple amides, indirect oxidations of amides have proven useful for synthesizing chiral starting materials. Such reactions are often employed when direct electrolyses... 

Condensation under the usual conditions gave in fact the pyrimidine (XCVI, R = P-CIC6H4) in only 10—15% yield. Even an excess of ethyl acetoacetate raised the yield only inconsiderably (to 30%), the rest of the product being a brown viscous oil, from which the supposed triazine (XCVII) (arising by N2,N -addition) was isolated. The alternative possible N N 5-addition would result in the theoretically possible structure (XCVIII). However, as Paludrine is known to react with ethyl formate at N2,N (372), it is assumed by analogy that ethyl acetoacetate reacts similarly. 

The metal-ligand interaction in S complexes should he comparable to that in other complexes with sulfur-containing ligands, at least for higher values of n. Additionally, the observation that polysulfides with even n prefer coordination to closed-shell metal ions and those with odd n to open-shell ones indicates that the kind of metal-to-ligand interaction is obviously not restricted to the sulfur atoms attached directly to the metal. 

A general type of chemical reaction between two compounds, A and B, such that there is a net reduction in bond multiplicity (e.g., addition of a compound across a carbon-carbon double bond such that the product has lost this 77-bond). An example is the hydration of a double bond, such as that observed in the conversion of fumarate to malate by fumarase. Addition reactions can also occur with strained ring structures that, in some respects, resemble double bonds (e.g., cyclopropyl derivatives or certain epoxides). A special case of a hydro-alkenyl addition is the conversion of 2,3-oxidosqualene to dammara-dienol or in the conversion of squalene to lanosterol. Reactions in which new moieties are linked to adjacent atoms (as is the case in the hydration of fumarate) are often referred to as 1,2-addition reactions. If the atoms that contain newly linked moieties are not adjacent (as is often the case with conjugated reactants), then the reaction is often referred to as a l,n-addition reaction in which n is the numbered atom distant from 1 (e.g., 1,4-addition reaction). In general, addition reactions can take place via electrophilic addition, nucleophilic addition, free-radical addition, or via simultaneous or pericycUc addition. 

To identify a gap Present-active [A]n additive that degrades slowly in the soil is required. (From Jozefaciuk et ak, 2003)... 

N,N-addition can be understood in terms of the size and spatial distribution of the HOMO (2A2, 19) and LUMO (4Bj, 20). Both orbitals are primarily sulfur-based, so that efficient overlap in the transition state is best achieved via addition at sulfur as opposed to nitrogen. 

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