Synthesis of 2-methyl-3-vinyl-1,4-naphthoquinones

Pyrethroid insecticides Chapter IVb. Selected transformations of chrysanthemic acid and its lower esters to Pyrethroid. Use of the Wittig and related reactions

“…The synthesis of the alkyltriphenylphosphonium salts has been routinely achieved on reaction of triphenylphosphine with the requested alkyl halide (Scheme 91). 86,200,201 The reaction works reasonably well with methyl-and n-alkyl halides, especially the iodides, as well as with isopropyl-and isobutyl-iodides. It has been successfully used to synthesize 14 C radiolabelled isopropyl phosphonium salt (Scheme 28).…”

Synthesis and anti-tubercular activity of N2-arylbenzo[g]isoquinoline-5,10-dione-3-iminium bromides

“…Yield 9.86 g (92%), mp 107.3-107.5 °C (lit. 22 13 C NMR δ C (63 MHz, CDCl 3 ) 12.4 (CH 3 ), 15.3 (CH 2 CN), 61.5 and 62.6 (OCH 3 ), 117.8 and 119.7 (C q ), 122.3 and 122.4 (C-5 and C-8), 125.4 (C q ), 126.0 and 126.7 (C-6 and C-7), 126.9 and 128.7 (C q ), 150.6 (2 × COMe). IR (KBr) ν max /cm −1 2932, 2248 (CN), 1676, 1587, 1357, 1270.…”

Lipophilic 1,4-naphthoquinone derivatives: synthesis and redox properties in solution and entrapped in the aqueous cubic liquid-crystalline phase of monoolein

“…Activation of an aromatic nucleus can be achieved in several ways, one of the simplest being, in the case of naphthoquinol, removing of a proton and utilization of the resulting ambident anion in a Claisen alkylation with an appropriately functionalized side-chain. Bondinell et al (1968) have developed the two general syntheses of 2-methyl-3-vinyl-1,4-naphthoquinones, both constructing the substituted vinyl chain via the Wittig reaction. Electrophilic allylation at the C 3 position of 2-methyl-1,4-hydronaphthoquinone with allyl, crotyl or prenyl bromide has been successfully developed by Tabushi et al (1979) to give a highly selective one-step preparation of the corresponding vitamin K 1 (or K 2 ) analogues by the use of ␤-cyclodextrin in dilute aqueous alkaline solution.…”