Internal strains

In comparison with the platinum catalysts, rhodium catalysts are much more reactive to effect addition of bis(catecholato)diboron even to non-strained internal alkenes under mild reaction conditions (Equation (5)).53-55 This higher reactivity prompted trials on the asymmetric diboration of alkenes. Diastereoselective addition of optically active diboron derived from (li ,2i )-diphenylethanediol for />-methoxystyrene gives 60% de (Equation (6)).50 Furthermore, enantioselective diboration of alkenes with bis(catecolato)diboron has been achieved by using Rh(nbd)(acac)/(A)-QUINAP catalyst (Equation (7)).55,56 The reaction of internal (A)-alkenes with / //-butylethylene derivatives gives high enantioselectivities (up to 98% ee), whereas lower ee s are obtained in the reaction of internal (Z)-alkenes, styrene, and a-methylstyrene. 

Siliranes are also formed by the reaction of the cyclotrisilane [2-(Me2NCH2)C6H4]6Si3 with terminal and strained internal olefins under mild thermal conditions. The products obtained from the thermolysis of the siliranes thus prepared suggest a thermal equilibrium of the silirane with the cyclotrisilane and the corresponding alkene. This observation provides evidence for an equilibrium between the silylene and the cyclotrisilane and, moreover, proves that free silylenes are involved in the silylene transfer reaction48. 

Smith, J.K., Esch, C.W. and Kuhn, R.E. (1972) Growth and development of larval Taenia crassiceps (Cestoda). I. Aneuploidy in the anomalous ORF strain. International Journal for Parasitology 2, 261-263. 

Gycloreversion to the vinylalkylidene is rarely observed directly, despite being a commonly proposed step in carbene or alkylidene/alkyne reaction cascades. Bridged titanacyclobutene complex 57, however, clearly resists the formation of a strained internal alkylidene from alkyne extrusion, equilibrating instead with vinylalkylidene complex 58, stabilized by the addition of trimethylphosphine (Equation 20) <2003ICA27>. This system provides a very rare simultaneous observation of interconverting metallacyclobutene and vinylalkylidene isomers. 

Thompson, R. C. A. Kumaratilake, L. M. (1985). Comparative development of Australian strains of Echinococcus granulosus in dingoes (Canis familiaris dingo) and domestic dogs (C.f familiaris), with further evidence for the origin of the Australian sylvatic strain. International Journal for Parasitology, 15 535-42. 

Summary New silacyclopropanes were synthesized quantitatively under mild thermal conditions by reaction of olefins with cyclotrisilane (cyclo-(Ar2Si)3, Ar = Me2NCH2QH4) 1, which transfers all of its three silylene subunits to terminal and strained internal olefins. Thermolysis of silacyclopropanes 3a und 3b indicated these compounds to be in a thermal equilibrium with cyclotrisilane 1 and die corresponding olefin. Silaindane 13 was synthesized by reaction of 1 with styrene via initially formed 2-phenyl-1-silacyclopropane 3d. Reaction of 1 with conjugated dienes such as 2,3-dimethyl-l,3-butadiene, 1,3-cyclohexadiene or anthracene resulted in the formation of the expected 1,4-cycloaddition products in high yield. 

I strain Internal strain that results from changes in ring strain in going from a tetrahedral to a trigonal carbon or vice versa. 

MANCINO, D. OVARY, Z. (1980) Adjuvant effects of amorphous silica and of aluminium hydroxide on IgE and IgGl antibody production in different inbred mouse strains. International Archives of Allergy and Applied Immunology, 61, 253-258. 

Balaji, S., Gopi, K.,Lavanya, B. and Muthuvelan, B. (2012) Isolation and optimization of poly p hydroxy-butyrate producing cyanobacterial strains. International Journal of Applied Biology and Pharmaceutical Technology, 3(1), 137-145. 

Green, A.E. and Naghdi, P.M. (1971) Some remarks on elastic-plastic deformation at finite strain. International Journal of Engineering Science, 9, 1219-1229. 

Hashmi, M. S. J. and Hamouda, A. M. S. Development of ID Constitutive Equations for Metals Subjected to High Strain Rate and Large Strains. International Journal of Strain Analysis 1994 29 117-27. 

Kibenich, A., Sprensen, K., Johansen, E. (2012). Texturizing lactic acid bacteria strains. International Patent Application WO/2012/052557. 

Aguilera, R, Peinado, R. A., Millan, C., Ortega, J. M., Mamicio, J. C. (2006). Relationship between ethanol tolerance, H -ATPase activity and the hpid composition of the plasma membrane in different wine yeast strains. International Journal of Food Microbiology, no, 34-42. 

A convenient way of storing and purifying the strained olefin bicyclo[2,2,0]hex-l(4)-ene is by formation of a platinum complex (776), whose structure has been confirmed by 2f-ray analysis. The olefin is readily liberated from (776) by carbon disulphide and undergoes the expected Diels-Alder reaction with cyclopentadiene. Addition of ethanol to (776) is accompanied by opening of the strained internal bond to give the metallocycle (777). ... 

To address more challenging aUcene substrates, Widenhoefer [127] showed in 2009 that cyclic ureas could be used as spedahzed substrates for the hydroureation of completely unactivated alkenes, including ethylene (as mentioned in Section 15.3.2), propylene, terminal alkenes, and the strained internal alkene of nor-bornene. Using the preferred chiral bis(gold)phosphine catalysts (68), enantiomeric excesses of up to 78% have been obtained for this challenging transformation (Scheme 15.85) [127]. 

Additionally, certain internal olefins can be copolymerized with CO, albeit at much reduced rates. For example, by employing 2-butene, low molecular weight oligomers of poly( 1,5-ketone) are obtained by a sequence of insertion and isomerization steps (54). Copolymers with strained internal olefins such as (functionalized) norbornene or norbornadiene can also be made (55). 

Attard, M.M. Hunt, G.W. 2004. Hyperelastic Constitutive Modeling Under Finite Strain. International Journal of Solids and Structures, 41, 5327-5350. 

The addition of resolved P-chiral hydrogen phosphinates to alkenes has been accomplished without significant loss of the stereochemistry at phosphorus (Scheme 4.84) [124]. This reaction was achieved with the use of a radical initiator. One of the attractive aspects of this chemistry was that it proceeded under solvent-free conditions. The reaction was regioselective for the anti-Markovnikov product, and fair to moderate yields of the alkyl-phosphinate were obtained. Generally, high yields of the alkylphosphinate were obtained for a host of terminal alkenes as well as strained internal alkenes such as norbomene. Internal alkenes were significantly less reactive and satisfactory conversions were only... 

Kim, S., Seol, E., Oh, Y.-K., Wang, G.Y., Park, S., 2009. Hydrogen production and metabolic flux analysis of metabolically engineered Escherichia coli strains. International Journal of Hydrogen Energy 34, 7417—7427. 

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