O-Bromonaphthalene

Kirin et al. (1965, 1967) and Kirin and Moskalev (1971) employed rare-earth acetates as the starting materials to prepare metal phthalocyaninates. It was demonstrated that apart from the monomeric half-sandwich complexes, the reactions also gave bis(phthalocyaninato) sandwich complexes, both of which remained poorly characterized at that time. These half-sandwich compounds are susceptible to de-complexation giving metal-free H2(Pc) upon heating in o-bromonaphthalene or treatment with concentrated sulfuric acid (Shklover and Plyushchev 1964). When a DMF solution of R(Pc)Cl is treated with NH4OH, R(Pc)(0H)-H20 is formed which is thermally unstable. Upon heating to 240°C, this compound converts to the dimeric species [R(Pc)]20 (Ni et al. 1987). 

Starting from 2-hydro yphenylboronic acid and o-bromobenzaldehyde or o-bromonaphthalene carboxaldehyde derivatives as substrates, a number of 6H-benzo[c]chromene-6-ones, 51f-naphtho[l,2-c]chrome-5-ones, and 6H-naphtho[2,l-c]chromene-6-one were synthesized in good yields (Scheme 3.44a). The overall transformation consists of three reactions Suzuki-Miyaura cross-coupling, hemi-acetal formation, and oxidation. By combining 6-diazo-2-cyclohexenone and 2-iodo methylbenzoate as substrates, benzo[c]chromen-6-ones were produced in good yields as well... 

Replacement of the diazo group by hydrogen has been reported for a number of diazo oxides. For example, the diazo oxide from 2-nitro-4-aminophenol yields o-nitrophenol in 53% yield,42 - 43 and that from 1-amino-2-hydroxy-6-bromonaphthalene-4-sulfonic acid gives XV in approximately 50% yield.44... 

The photostimulated carbonylation of aryl and vinyl halides by Co(CO)4" ions under phase-transfer catalysis conditions [Co2(CO)8, C6H6/NaOHaq, CO, Bu4N+Br", 65 °C] has been reported211,212. Thus PhBr, o- and /7-bromo toluenes, /7-bromoanisole, p-bromofluorobenzene, 4-bromoacetophenone and 1- and 2-bromonaphthalenes gave ArC02Na in 90-98% yields. Under the conditions used, carbonylation did not occur with unsubstituted PhCl, but when it was substituted, as in / -chlorobenzoic acid, or p-chlorophenylacetic acid, carbonylation was quantitative (98% yield). 

Bromo-4-methoxytoluene, 26, 51 o-Bromo- -methylanisole, 23, 12 < -BR0M0-/3-METHYLVALERIC ACID, 21, 61 a-Bromonaphthalene, 21, 89... 

Bromonaphthalene has been prepared from 2-aminonaphtha-lene by the reaction of mercuric bromide with the diazonaphtha-lene. The reaction described in this preparation appears to be fairly general and provides a useful alternative method for introducing bromine into the aromatic nucleus. Using conditions similar to those outlined, the following have been prepared from the corresponding aryl alcohols a-bromonaphthalene (72%), 3-bromopyridine (76%), 2-bromopyridine (61%), 8-bro-moquinoline (48)%, o-bromotoluene (72%), />-chlorobromo-benzene (90%), -nitrobromobenzene (60%), and />-methoxy-bromobenzene (59%). The use of the triphenylphosphine-halogen complex to convert alcohols to alkylhalides is described elsewhere in this series. ... 

Water Glycerol Formamide Thiodigylcol Methylene iodide sym-T etrabromoethane 1 -Bromonaphthalene o-Dibromobenzene 1 -Methy Inaphthalene Dicyclohexyl n-Hexadecane n-Decane... 

Alkoxynaphthalenes are converted to 1-chloro- or l-bromo-2-alkoxynaphtha-lenes in near quantitative yield using copper(II) chloride or bromide. 1-Alkoxy-naphthalene affords about 70% l-alkoxy-4-bromonaphthalene with copper(II) bromide. Similarly, anisole gives a mixture of o- and p-haloanisoles. The absence of meta isomer is believed to provide evidence for the intermediacy of a radical cation of anisole.127)... 

Halogenated aromatics Chlorinated benzenes (Cl2 - Cl5) 1 -Chloronaphthalene Dichloronaphthalene (3 isomers) 1 -Bromonaphthalene o ... 

---