환상 Keto Ester로부터 Naphthalene 유도체의 합성 = Syntheses of Naphthalene Derivatives from Cyclic Keto Esters

국문 초록 (Abstract)

3,4-Dihydro-3-methoxycarbonyl-1(2H)-naphthalenone〔1〕과 3,4-dihydro-2-ethoxy-carbonyl-1(2H)-naphthalenone〔9a〕를 각각 Grignard 시약과 반응을 시켜, 1,3-및 1,2-dialkylnaphthalen과 3종의 naphthothiophene 유도체를 합성하였다.
환상 r-Keto ester〔1〕과 Grignard 시약과의 반응에서는 예상했던 diol〔2〕, keto alcohol 〔3〕및 1,2,3,4-tetrahydro-1,1-dimethylnaphthalene-3-carboxylic acid [4a]의 혼합물을 얻었다. [2]와 [4]로부터 3-isopropyl-1-methylnapthalene[7a〕를, 〔3〕으로부터는 3-ispropyl-1-naphthol〔7b〕를 합성하였다.
한편 환상 B-keto ester〔9a〕의 Grignard 반응에 의한 생성물은 예상했던 keto alcohol〔10〕이었으며, 그의 탈수반응으로 공액불포화 ketone〔11a〕를 얻을 수 있었다. 〔11a〕와 Grignard 시약으로부터 1,2,3,4-tetrahydro-1-methylene-2-isopropylidenenaphthalene 〔12〕와 3,4-dihydro-2t-bytyl-1(2H)naphthalenone〔13〕을 얻었다. 또, 〔12〕와 〔13〕으로 부터는 각각 2-isopropyl-1-methylnaphthalene〔7c〕와 2-t-butyl-1-methylnaphthalene 〔7c〕와 2-t-butyl-1-methylnaphthalene〔7e〕를 합성하였다.
〔7a〕의 피크르산염은 녹는 점이 문헌과 다르게 나타났으므로, 〔9a〕의 4-methyl 유도체로부터 별도로 합성하여 확인하였다.
또, 황으로 탈수소시킬 때 부산물로 얻은 naphtho〔1,2-b〕thiophene〔8〕과〔15〕및 naph-tho〔1,2-c〕thiophene〔14〕의 구조도 검토하여 보았다.

다국어 초록 (Multilingual Abstract)

3,4-Dihydro-3-methoxycarbonyl-1(2H)-naphthalenone〔1〕and 3,4-dihydro-2-ethox-ycarbonyl-1(2H)-naphthalenone 〔9a〕were allowed to react with methylmagnesium iodide, and from their products 1,3-or 1,2-dialkylnaphthalenes and three naphtho-thiophene derivatives were synthesized.
The reaction of 〔1〕with Grignard reagent yielded a mixture of the expected diol〔2〕, keto alcohol〔3〕, and 1,2,3,4-tetrahydro-1,-1-dimethylnaphthalene-3-carboxylic acid〔4a〕. By heating〔2〕 with sulfur, 3-isopropyl-1-methylnaphthalene〔7a〕 was obtained.
On the other hand, 〔9a〕reacted with Grignard reagent to yield the desired keto alcohol〔10〕. When it was dehydrated, a,B-unsaturated ketone〔11a〕was obtained.
The melting point of picrate of 〔7a〕was 105.5~106.5℃, but that shown in the literature is 84℃. In order to identify the hydrocarbon〔7a〕, it was also synthesi-zed from 4-methyl derivative of〔9a〕, and in this synthesis 3,5-dimethylnaphtho〔1,2-b〕thiophene〔15〕was obtained as a by-product.