TY - JOUR
T1 - Asymmetric Synthesis of AB Rings in ent-Kaurene Carbon Framework
AU - Ma, Wenjing
AU - Zhu, Lizhi
AU - Zhang, Mengxun
AU - Lee, Chising
N1 - Funding Information:
* Corresponding authors. E-mail: [email protected]; [email protected] Received August 17, 2021; revised September 16, 2021; published online October 14, 2021. Project supported by the Anhui University Natural Science Foundation-Funded Project (No. KJ2020B19), and the Chuzhou University Initial Funding (No. 2018qd06). 安徽省高校自然科学一般项目(No. KJ2020B19)、滁州学院启动基金(No. 2018qd06)资助项目.
Publisher Copyright:
© 2022 Chinese Chemical Society & SIOC, CAS.
PY - 2022/2
Y1 - 2022/2
N2 - The total synthesis of ent-kaurene natural products of Xerophilusin I, Neolaxiflorin L, Eriocalyxin B, 15-epi- Enmelol completed by diversity-oriented synthesis strategy. In this paper, the regioselectivity of Horner-Wadsworth-Emmons reaction was optimized, and a single Z configuration was transformed from Z/E mixture under acidic condition. Based on the conversion of a single configuration under mild acidic conditions, a mechanism for hydrogen bond-assisted Michael addition/retro-Michael elimination is proposed. The asymmetric Diels-Alder reaction with silylenol ether dienyl 3 and β-ketoate 1 as dienophile was developed. Using Cu(OTf)2 as Lewis acid and oxazoline as chiral ligand, AB-ring-skeleton was constructed with 65% yield and >19:1 dr value.
AB - The total synthesis of ent-kaurene natural products of Xerophilusin I, Neolaxiflorin L, Eriocalyxin B, 15-epi- Enmelol completed by diversity-oriented synthesis strategy. In this paper, the regioselectivity of Horner-Wadsworth-Emmons reaction was optimized, and a single Z configuration was transformed from Z/E mixture under acidic condition. Based on the conversion of a single configuration under mild acidic conditions, a mechanism for hydrogen bond-assisted Michael addition/retro-Michael elimination is proposed. The asymmetric Diels-Alder reaction with silylenol ether dienyl 3 and β-ketoate 1 as dienophile was developed. Using Cu(OTf)2 as Lewis acid and oxazoline as chiral ligand, AB-ring-skeleton was constructed with 65% yield and >19:1 dr value.
KW - Asymmetric Diels-Alder reaction
KW - Ent-kaurane
KW - Horner-Wadsworth-Emmons reaction
KW - Regioselectivity
KW - Homer-Wadsworth-Emmons reaction
KW - regioselectivity
KW - ent-kaurane
KW - asymmetric Diels-Alder reaction
UR - http://www.scopus.com/inward/record.url?scp=85126314132&partnerID=8YFLogxK
U2 - 10.6023/cjoc202108029
DO - 10.6023/cjoc202108029
M3 - Journal article
AN - SCOPUS:85126314132
SN - 0253-2786
VL - 42
SP - 580
EP - 589
JO - Chinese Journal of Organic Chemistry
JF - Chinese Journal of Organic Chemistry
IS - 2
ER -