Tetrakis methane, synthesis

Tetrahalosulphones, reactions of 417 Tetrakis(alkylsulphinylmethyl)methanes 575 Thiacyclohexanes, reactions of 599 Thiacyclo[3.3.0]octane oxides, synthesis of 607... 

AO containing various phenolic moieties were prepared by transesterification in the presence of tetraalkyl titanates. Randomly distributed -active moieties are characteristic of 140 (only the hard polyester segment is given) prepared from dimethyl terephthalate, 1,4-butanediol, poly(tetramethylene oxide)diol and dimethyl 5-(3,5-di-tm-butyl-4-hydroxybenzenepropaneamido)isophthalate [181]. The mentioned polymeric AO was used for stabilization of polyether-polyester elastomers. A partial attachement of tetrakis[methylene 3(3,5-di-tert-butyl-4-hydroxy-phenyl)propionate]methane (3) via transesterification reaction was expected in the synthesis of another polyether-polyester elastomer by [182]. A reversible redox polyester was formed from 2,5-bis(2-hydroxyethyl)hydroquinone and dichlorides of aliphatic dicarboxylic acids [137],... 

The synthesis of tetrakis(2-thienyl)methane also depends on this synthesis method in its final stage. ... 

The art and science of organic synthesis encompasses an enormous range of activities in which synthesis of the designed symmetric molecules is an aesthetically pleasing endeavor. We have synthesized (Scheme 30.22), a structurally unique and symmetric, nonnatural product, tetrakis(cyclopropylmethyl)methane (129) and studied its conformation by singlecrystal x-ray as well as by low-temperature NMR spectroscopy. 

The general procedure for the synthesis of 9-15 is shown in Scheme 1. Bromobenzene 1 was prepared accotding to Bickelhaupt et al. [3], and the novel bromobenzene 2 was synthesized by the reaction of two equivalents of sodium methane thiolate with one equivalent of 2,6-bis(bromomethyl)bromobenzene. Compounds 1 and 2 were then converted with butyllithium to the corresponding litfaialed species which reacted with one equivalent of either methyidichlorosilane, phenyldichlorosilane or dimethyldichlorosilane to afford the chlorosilanes 3-8. The chlorosilanes were then treated with one equivalent of trimethylsilyl triflate to yield the silyl triflates 9-14. Silyl triflate 10 could also be prepared by the reaction of chlorosilane 4 with one equivalent of triflic add. The silyl tetralds(pentafluorphenyl)borate 15 was synthesized by the reaction of chlorosilane 4 with one equivalent of lithium tetrakis(pentafluorphenyl)borate. Compounds 9-15 are dissodated in dichloromethane solution. 

The benefit of multivalent interactions over monovalent interactions in various branches of the life sciences has been well established. It is known as the cluster effect or dendritic effect. Pentaerythritol [1, tetrakis(hydroxymethyl)methane, 2,2-bis(hydroxymethyl)l,3-propanediol] is a scaffold widely used in the synthesis of glycoclusters and glycodendrimers. It can be derivatized to allow preparation of a... 

Scheme 5-151. Synthesis of a tetrakis(4-ethynylphenyl)methane-based polymer...

Scheme 7.41 Synthesis of porous organic polymers by CuAAC reaction between tetrakis(4-azidophenyOmethane and tetrakis(4-ethynylphenyl)methane.

The synthesis of spiroacetals was improved by using new simple and readily accessible Rh(COD)2 complexes that allowed excellent conversions and an overall reduction of reaction times [33]. Moreover, very recently a dual metal catalytic system (Rh(l) and lr(I)) was successfully utilized for these reactions on alkynediols, and in some cases it works more efficiently than the single metal catalyst [34]. The combination of the two metal complexes ([Rh(bpm)(CO)2]BAr4 and [Ir (bpm)(CO)2]BAr4 (bpm = bis(l-pyrazolyl)methane, BAt4 = tetrakis[3,5-bis (trifluoromethyl)phenyl]borate) acted cooperatively to promote an efficient dual activation pathway for both the 5-exo and 6-endo cyclization in which the Rh(I) preferentially promotes the 6-membered ring formation, while the Ir(I) in preference promotes the 5-membered cyclization of alkynediols. 

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