Propane, 2,2-bis

A DNA duplex containing an interstrand dithio-bis-propane cross-link between two central adenosine residues has been solved by crystallographyThe cross-link is long enough so that it does not cause helical bending. 

C2aH3oBr3C02NftOa, (Bis(propane-1,3-diyl)-di(5-methylphalaldimin-2-olato) )aquobromocobalt(II)-aquobromocobalt(111) bromide (orthorhombic), 41B, 974... 

C2 5H2 aCoNftOa, Dioxygen(N,N -(2-(2 -pyridyl)ethyl)ethylenebis(sali-cylideneiminato))cobalt acetonitrile solvate, 44B, 839 C2sH27ClN303Ti, N,N -Ethylenebis(salicylideneiminato)chloropyridine-titanium(III) tetrahydrofuran solvate, 44B, 840 C2 5H2 7C0N3O3, N,N -(2-(2 -Pyridyl)ethyl)ethylenebis(salicylideneim-inato)cobalt(II) ethanol solvate, 44B, 839 C2 5H3oBr2C02Nft03, (Bis(propane-1,3-diyl)-di(5-methylphalaldimin-2- olato))bis(bromocobalt(II)) methanol solvate, 41B, 976 C2 sHi8ClFeN202S2, Chloro(bis(salicylideniminephenyl)disulfido)iron-... 

C5H15CI2C0O2.5, Cobalt chloride methanol, 43B, 1351 CgHi2CUN2O4, Bis(propane-2-nitronato)copper(II), 39B, 761 CgHi2CuOioS, Tris(1,2-ethanediol)copper(II) sulfate, 38B, 949 C6Hi20sW, Tris(ethylene-1,2-dioxo)tungsten(VI), 40B, 932 CgHi4BrCuNO, (2-Diethylaminoethanolato)copper(II) bromide, 37B, 561... 

CA. . .. methanetetraylbis... trad. NyN -Diisopropylcarbodiimide new Methanedi(ylidene)bis(propan-2-ylazane)... 

Chlorides are inert. However, the reaction ofp-chlorobenzophenone (9) with a styrene derivative proceeds satisfactorily at 150 C by u.sing dippb [l,4-bis(-diisopropylphosphino)butane] as a ligand to give the stilbene derivative 10. However, dippp [l,3-bis(diisopropylphosphino)propane] is an ineffective ligand[13]. On the other hand, the coupling of chlorobenzene with styrene proceeds in the presence of Zn under base-free conditions to afford the cis-stilbene 11 as a main product with evolution of H . As the ligand, dippp is... 

Usually, iodides and bromides are used for the carbonylation, and chlorides are inert. I lowever, oxidative addition of aryl chlorides can be facilitated by use of bidcntatc phosphine, which forms a six-membered chelate structure and increa.scs (he electron density of Pd. For example, benzoate is prepared by the carbonylation of chlorobenzene using bis(diisopropylphosphino)propane (dippp) (456) as a ligand at 150 [308]. The use of tricyclohexylphosphine for the carbonylation of neat aryl chlorides in aqueous KOH under biphasic conditions is also recommended[309,310]. 

The reaction of cyclohexene with the diazopyruvate 25 gives unexpectedly ethyl 3-cyclohexenyl malonate (26), involving Wolff rearrangement. No cyclo-propanation takes place[28]. 1,3-Dipolar cycloaddition takes place by the reaction of acrylonitrile with diazoacetate to afford the oxazole derivative 27[29]. Bis(trimethylstannyl)diazomethane (28) undergoes Pd(0)-catalyzed rearrangement to give the A -stannylcarbodiimide 29 under mild conditions[30]. 

Polycarbonate is a polyester in which dihydric (or polyhydric) phenols are joined through carbonate linkages. The general-purpose type of polycarbonate is based on 2,2-bis(4 -hydroxybenzene)propane (bisphenol A) and has the general structure ... 

Pis commonly have been synthesized from reactions of pyromellitic dianhydride [26265-89-4] (PMD A) or 3,3H,4 -benzophenone tetracarboxyUc dianhydride [2421-28-5] (B IDA) with a number of diamines like 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-amino-3-methylphenyl)propane, I,I-bis(4-aminophenyl)-I-phenylethane, and 1,1-his(4-amino-3-methy1pheny1)-1-phenylethane (5). The PMDA-based Pis were thermally more stable than the corresponding Pis obtained from BTDA. 

A.ntioxidants. PhenoHc antioxidants, added at about 0.1—0.5 phr, are usually chosen from among butylated hydroxytoluene [128-37-0] (BHT), and Nnonylphenol [104-40-5] for Hquid stabilizer formulations and bisphenol A [80-05-7] (2,2-bis-(/)-hydroxyphenyl)propane) for the soHd systems. Low melting thioesters, dilauryl thiodipropionate [123-28-4] (DLTDP) or distearyl thiodipropionate [693-36-7] (DSTDP) are commonly added along with the phenoHcs to enhance their antioxidant performance. Usually a 3 1 ratio of thiodipropionate to phenoHc antioxidant provides the desired protection. Most mixed metal stabilizer products contain the antioxidant iagredient. 

The most important commercial chemical reactions of phenol are condensation reactions. The condensation reaction between phenol and formaldehyde yields phenoHc resins whereas the condensation of phenol and acetone yields bisphenol A (2,2-bis-(4-hydroxyphenol)propane). PhenoHc resins and bisphenol A [80-05-7] account for more than two-thirds of U.S. phenol consumption (1). 

An example is poly(bis(p-carboxyphenoxy)propane) (PCPP) which has been prepared as a copolymer with various levels of sebacic anhydride (SA). Injection molded samples of poly (anhydride) / dmg mixtures display 2ero-order kinetics in both polymer erosion and dmg release. Degradation of these polymers simply releases the dicarboxyhc acid monomers (54). Preliminary toxicological evaluations showed that the polymers and degradation products had acceptable biocompatibiUty and did not exhibit cytotoxicity or mutagenicity (55). 

The most common commercial polycarbonate [24936-68-3] is prepared from 2,2-bis (4-hydroxyphenyl)propane, that is, bisphenol A [80-05-7] and has the general stmcture ... 

Alkyl- and aryl-pyridazines can be prepared by cross-coupling reactions between chloropyridazines and Grignard reagents in the presence of nickel-phosphine complexes as catalysts. Dichloro[l,2-bis(diphenylphosphino)propane]nickel is used for alkylation and dichloro[l,2-bis(diphenylphosphino)ethane]nickel for arylation (78CPB2550). 3-Alkynyl-pyridazines and their A-oxides are prepared from 3-chloropyridazines and their A-oxides and alkynes using a Pd(PPh3)Cl2-Cu complex and triethylamine (78H(9)1397). 

Joining two heteroatoms to a ring by radical combination is not presently a common route to heterocycles. It might become more important if the art of metal-catalyzed redox reactions keeps advancing at the present pace. Current examples are the conversion of 1,5-dithiols to 1,2-dithiepanes by oxidants such as FeCla, and the oxidation of 1,3-propane-bis-hydrazines to 1,2,3,4-tetrazepines (Sections 5.18.4.1 and 5.18.10.1). 

In addition several other materials have been reported by industrial companies, but have not at the time of writing been commercialised. These include the product of condensation of 2,2-bis-(p-aminocyclohexyl)propane (VI) (Figure 18.28) with a mixture of adipic and azelaic acid (Phillips Petroleum), a research material produced in the old German Democratic Republic obtained by melt condensation of /ranj -cyclohexane-l,4-dicarboxylic acid (VII) (Figure 18.28) and the two trimethylhexamethylenediamine isomers used in the manufacture of Trogamid T, and another amorphous material (Rilsan N by Ato Chimie). 

A polyether-amide with a heat distortion temperature of 198°C has been prepared by Hitachi by interfacial polycondensation of 2,2-bis-[4-(4-aminophen-oxy)phenyl]propane (VIII) with a mixture of isophthaloyl- and terephthaloyl-chloride (IX and X) (Figure 18.29). 

As already indicated, the polycarbonates may be produced from a wide range of polyfunctional hydroxy compounds. In practice only the diphenyl compounds have proved of much interest and the only polycarbonate of commercial significance is derived from bis-phenol A 2,2-bis-(4-hydroxyphenyl) propane. 

To enhance flame retardancy without use of additives, 2,2-bis-(3,5-dibromo-4-hydroxyphenyl)propane (tetrabromobis-phenol A) has been used in copolymers with bis-phenol A. 

Compound 1 is used as a solvent in the food, paint, resin/plasties, soap and woodpulp/paper industries, and as a plastieizer. Compound 2 is used as an intermediate for the manufaeture of hydraulie fluid additives and eosmeties. Sulphonal (2 2-bis(ethylsulphonyl)-propane), another important sulphone, is a eolourless solid, stable to aeids and alkalis, with hypnotie properties. 

---