Synthetic Study of Macrocyclic Terpenoids by the Pummerer-type alpha-Allylation of Chiral Selenoxides

手性硒氧化物的Pummerer型α-烯丙基化合成大环萜类化合物的研究

• 批准号: 06650995
• 负责人: SHIMADA Kazuaki
• 金额: $ 1.22万
• 依托单位: Iwate University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06650995/
• 关键词: Selenoxide; Pummerer reaction; alpha-Allylation; Allylsilane; Steric protection; Selenonium ion; Thermal syn elimination; Carbon chain homologation; プンメラ-反応; 熱的syn脱離反応; 大環状化合物; Xeniaジテルペノイド; 分子内閉環反応; 光学活性セレノキシド; 2-フェニルセレノ酢酸エステル; プンメラ-型アリル化反

A CH_2Cl_2 solution of l-menthyl 2-phenylselenenylacetates (1a) was treated with mCPBA to give the corresponding selenoxide 2a as stable colorless needles. The ^1H NMR and ^3CNMR spectra of 2a indicated that 2a was obtained as an equilibrated 1 : 1 mixture at the Se-O bond. On the other hand, mCPBA oxidation of the ethyl 2-phenylselenenylacetate (1b) only gave the recoverted selenide due to the deoxygenation from the selenoxide 2b during the usual workup. Thus, it was obvious that the steric protection was effectvie for the stabilization of seleninyl functionality.Subsequently, a CH_2Cl_2 solution of 2a was treated with (CF_3CO)_2O or BF_3・OE_<t2> in the presence of allyltrimethylsilane to affod an inseparable diastereomeric mixture (1 : 1) of the alpha-allylation products (l-menthyl 2-phenylselenenyl-4-pentenoate (3a)) besides selenide 1a and diphenyl diselenide. One-pot alpha-allylation of 2b was also carried out by the stepwise treatment of 1b with mCPBA,allyltrimethylsilane, and (CF_3CO)_2O.The use of the allyltributylstannanes was also effective for the similar alpha-allylation of 2a, but the unavoidable contamination of organostannanes to the crude reaction mixture made the chromatogaphic purification of the products so difficult. The alpha-allylation of selenoxides 2 was thought to proceed through the nucleophilic attack of allylsilane to the selenonium ion generated by the Pummerer type reaction from 2.Furthermore, mCPBA oxidation of the diastereomeric mixture of 3a gave l-menthyl (2E)-2,4-pentadienoate (4a) through thermal syn elimination of selenoxides. Thus, the Pummerer-type alpha-allylation of selenoxides 2 was regarded as being a novel homologation reaction of carbon chains.

L薄荷酯-2-苯基硒基乙酸酯(1a)的CH2Cl2溶液与mCPBA反应得到相应的氧化硒2a作为稳定的无色针。2a的~1H核磁共振和~3CNMR谱表明，2a在Se-O键处以1：1的平衡混合物形式存在。另一方面，mCPBA氧化2-苯基硒基乙酸乙酯(1b)只得到回收的硒，这是因为在通常的操作过程中，氧化硒2b会脱氧。随后，在烯丙基三甲基硅烷存在下，用(Cf_3CO)_2O或BF_3·oe_&lt；t2&gt；与2a的CH_2Cl2溶液反应，生成了除硒1a和二苯二烯外的1：1的α-烯丙化产物(L-薄荷基-2-苯基硒-4-五烯酸酯(3a))。用mCPBA、烯丙基三甲基硅烷和(CF3CO)2O对1b进行一锅法α-烯丙化反应也是有效的，但由于有机锡类化合物不可避免地污染到粗反应混合物中，使得产物的层析纯化变得困难。2的α-烯丙基化反应是通过烯丙基硅烷对Pummerer型反应生成的Se离子的亲核攻击进行的。此外，3a的非对映异构体混合物经热同步消除得到L-薄荷酯(2E)-2，4-戊二烯酸酯(4a)。因此，Pummerer型硒氧化合物2的α-烯丙基化反应被认为是一种新的碳链同源反应。

项目成果

Kazuaki Shimade, Akihiro Otaki, Masaki Yanakawa, Shosuke Mabuchi, Naoya Yamakado, Kazuya Inoue, Takeshi Shimoguchi, Takashi Kagawa, Kazutoshi Shoji, and Yuji Takikawa,: "A Pummerer-type Novel Ring Fission of 2-Methysulfinyl-5,6-dihydro-4H-1,3,4-thiadiazin

Kazuaki Shimade、Akihiro Otaki、Masaki Yanakawa、Shosuke Mabuchi、Naoya Yamakado、Kazuya Inoue、Takeshi Shimoguchi、Takashi Kakawa、Kazutoshi Shoji 和 Yuji Takikawa，“2-甲基亚磺酰基-5,6-二氢的普默勒型新型环裂变”

Kazuaki Shimade, Akihiro Otaki, Masaki Yanakawa, Shosuke Mabuchi, Naoya Yamakado, Kazuya Inoue, Takeshi Shimoguchi, Takashi Kagawa, Kazutoshi Shoji, and Yuji Takikawa,: "A Homologation of Aldehydes and Ketones via the Formation and the Subsequent Pummerer

Kazuaki Shimade、Akihiro Otaki、Masaki Yanakawa、Shosuke Mabuchi、Naoya Yamakado、Kazuya Inoue、Takeshi Shimoguchi、Takashi Kakawa、Kazutoshi Shoji 和 Yuji Takikawa，：“通过形成和随后的普默勒实现醛和酮的同源化

Kazuaki Shimada, Akihiro Otaki, Masaki Yanakawa, Shosuke Mabuchi, Naoya Yamakado, Kazuya Inoue, Takeshi Shimoguchi, Takashi Kagawa, Kazutoshi Shoji, and Yuji Takikawa: "A Pummerer-type Novel Ring Fission of 2-Methylsulfinyl-5,6-dihydro-4H-1,3,4thiadiazine

Kazuaki Shimada、Akihiro Otaki、Masaki Yanakawa、Shosuke Mabuchi、Naoya Yamakado、Kazuya Inoue、Takeshi Shimoguchi、Takashi Kakawa、Kazutoshi Shoji 和 Yuji Takikawa：“2-甲基亚磺酰基-5,6-二氢-的普默勒型新型环裂变”

Kazuaki Shimada, Akihiro Otaki, Masaki Yanakawa, Shosuke Mabuchi, Naoya Yamakado, Kazuya Inoue, Takeshi Shimoguchi, Takashi Kagawa, Kazutoshi Shoji, and Yuji Takikawa: "A Homologation of Aldehydes and Ketones via the Formation and the Subsequent Pummerer-

Kazuaki Shimada、Akihiro Otaki、Masaki Yanakawa、Shosuke Mabuchi、Naoya Yamakado、Kazuya Inoue、Takeshi Shimoguchi、Takashi Kakawa、Kazutoshi Shoji 和 Yuji Takikawa：“通过形成和后续的 Pummerer 实现醛和酮的同源化 -

Kazuaki Shimada,Akihiro Otaki,Masaki Yanakawa,Shosuke Mabuchi,Naoya Yamakado,Kazuya Inoue,Takeshi Shimoguchi,Takashi Kagawa,Kazutoshi Shoji,and Yuji Takikawa: "A Homologation of Aldehydes and Ketones via the Formation and the Subsequent Pummerer-type Ring

Kazuaki Shimada、Akihiro Otaki、Masaki Yanakawa、Shosuke Mabuchi、Naoya Yamakado、Kazuya Inoue、Takeshi Shimoguchi、Takashi Kakawa、Kazutoshi Shoji 和 Yuji Takikawa：“通过形成和随后的普默勒型环实现醛和酮的同源化