Related Experiment Video
Updated: Oct 1, 2026
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
[Use of crystal conversion reactions in the synthesis of pentacyclic alkaloid analogues]
Abstract:
During investigation of substitution of debenzorutaecarpine derivatives thermal cyclization reactions was observed to produce new fused heterocyclic systems. The optimal temperature of cyclizations was determined by differential calorimetric measurements of crystals of intermediate products. The thermolysis of 2-azido-3-formil-debenzorutaecarpine gave, after elimination nitrogen, izooxazolo-debenzorutaecarpine in good yield. The cyclization of the 2-azido-3-nitroso-debenzorutaecarpine readily led to oxadiazolo E-ring analogue of rutaecarpine. The thermal cyclization of 2-hydroxy-debenzorutaecarpines gave 2-oxo- and 4-oxo-pyrano E-ring analogues of rutaecarpine. The structure of substances was confirmed by spectroscopic methods. The synthesised compounds are considered as first representatives of new heterocyclic ring systems.
Related Concept Videos
Cycloaddition Reactions: Overview
Pericyclic Reactions: Introduction
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic rearrangements are...
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Preparation of Alkynes: Dehydrohalogenation
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.

