Potassium naphthalide

Subsequently the intercalates - without prior ejqposure to air - were reduced either by hydrogen gas or using potassium naphthalide in THF. (3U) Clearly the choice of intercalation and reduction temperature will control the nature of the final product. These materials were then e qposed to air. Some of the results obtained are given in Table IV. Clearly catalyst B in its hi conversion and selectivity to acetylene demonstrates mique properties. 

When naphthalene is reduced in liquid ammonia by metallic potassium, evaporation of excess ammonia gives the solvated solid potassium naphthalide (K2 ... 

Other methods that use 55 anions as precursor for the synthesis of fullerene-derivatives usually involve chemical formation of the anion. Alkylation of 55 has been accomplished, e.g. by reduction with propanethiol and potassium carbonate in DMF [91,92], sodium methanethiolate in acetonitrile [93], the naphthalene radical anion in benzonitrile[94], potassium naphthalide [95] or simply with zinc [96]. 

When naphthalene is reduced in liquid ammonia by metallic potassium, evaporation of excess ammonia gives the solvated solid potassium naphthalide (K2. NH3. Naphth2). If sodium is used in place of potassium, the product detonates as crystallisation starts. This is attributed to energetic expulsion of ammonia held... 

The reaction is spontaneous if a reverse potential is applied or the cell is short circuited. Low alkali metal concentrations are obtained by using solutions of salts such as sodium or potassium naphthalide in THF or n-butyllithium in hexane ... 

Other chemical reagents that give lower alkali metal activities, for example, sodium and potassium naphthalide and benzophenone solutions in tetrahydroffiran (THF), have been used Examples of lithium reagents with different activities are shown in Figure 5. 

It has been proved that potassium naphthalide cleaves carbon-carbon bonds in various diphenylmethanes (26) and the cleavage of carbon-carbon bonds in... 

For this latter reaction, it should be noted that the use of potassium naphthalide leads to further reduction to K2[W(CO)5j thus, the milder reductant Na[Ph2CO] selectively leads to a less reduced complex [61]. M[Ph2CO] salts have instead been used in catalytic amounts as mediators (see Section 4.4). They are prepared by reduction of benzophenone in THF, DME, or ammonia by pieces of alkali metals (Li, Na, K) [68] ... 

If the latter reaction is performed with the very strong reductant potassium naphthalide instead of potassium acenaphthylenide which is milder, it leads to decomposition as a result of over-reduction [58]. 

A 160 ml solution of potassium naphthalide (67 mg naphthalene, 20 mg potassium) is titrated under stirring in an inert atmosphere and room temperature with a solution of monohydroxy poly(ethylene glycol) of molecular weight 5,000 (1 g, 0.2 mmol) in freshly distilled tetrahydrofiiran (5 ml) until the typical dark green colour disappears. 

In the same way, well-defined and narrow molecular weight distribution macrotydic poly(2-vinylnaphthalene) (P2VN) with DP up to 120 and poly(9,9-dimethyl-2-vinylfluorene) (PDMVF) with DP = 140 were prepared from potassium naphthalide (K-Naph)-initiated polymerization of 2VN or DMVF in THF at -78 °C. End-to-end coupling of the resulting dianions was achieved under high-dilution conditions (10 -10" M) with l,4-bis(bromomethyl)... 

Fig. 60 Scheme of synthesis of the junction-point reactive block copolymer PS-TEOS-PEO on a silicon wafer. AGE allyl glycidyl ether, TEOS triethoxysilane, TEA triethylamine, K Np potassium naphthalide (see text for details) [237c]... 

Pentafluorotoluene undergoes conventional nucleophilic displacement at the 4-position when it is treated with 9-phenylfluoren-9-yl-, 9-ethylfluoren-9-yl-, triphenylmethyl-, and phenylxanthenyl-potassium, but treatment with radical-anion reagents (potassium naphthalide or potassium biphenylide) gives low yields of 4,4 -dimethyloctafluorobiphenyl. One-electron... 

PPP can be doped with alkali metals as the electron-donor to provide highly conducting n-type materials with a metallic-gold appearance [4,186]. Thus, when a PPP pellet was treated with a potassium naphthalide solution in THF for about 100 hours, the conductivity of PPP increased from less than 10 S cm to a plateau value of about 30 S cm [4,186]. 

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