𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Effect of substituents at position 4 on the stereospecific polymerization of 1,3-diolefins. Polymers with a 1,2 isotactic structure from 4-methyl-1,3-pentadiene

✍ Scribed by L. Porri; M.C. Gallazzi

Publisher
Elsevier Science
Year
1966
Tongue
English
Weight
551 KB
Volume
2
Category
Article
ISSN
0014-3057

No coin nor oath required. For personal study only.

✦ Synopsis

Abstraet--4.Methyl-l,3-pentadiene has been polymerized by heterogeneous catalysts from AI(C2Hs) 3 and either TIC14, TIC13 or VCI3, to give polymers having almost exclusively 1,2 units, and showing crystallinity attributable to 1,2 isotactic sequences.

Homogeneous systems from AI(C2Hs)3 and either a titanium tetraalkoxide or a vanadyl trialkoxide yield from the same monomer polymers, which, although almost 100 per cent 1,2, are amorphous by X-ray examination.

Infra-red and X-ray analyses indicate that the 1,2 isotactic polymers of 4-methyl-l,3-pentadiene exist in two crystalline modifications.

The different results obtained from 4-methyl-l,3-pentadiene as compared with butadiene in the polymerization by each of the above systems, are interpreted on the basis of steric effects caused by the methyl groups on position 4. * X-ray structure has been studied by Prof. I. W.

📜 SIMILAR VOLUMES

Polymerization of 4-Methyl-1,3-pentadien
Polymerization of 4-Methyl-1,3-pentadiene with Catalysts Based on Cyclopentadienyl Titanium Chlorides: Effect of anti/syn Isomerism of the Allylic Group on the Chemoselectivity and the Role of Backbiting Coordination in 1,3-Diene Polymerization
✍ Cecilia Cugini; Ottavio A. Rombolà; Antonino Giarrusso; Lido Porri; Giovanni Ric 📂 Article 📅 2005 🏛 John Wiley and Sons 🌐 English ⚖ 117 KB

## Abstract **Summary:** Homopolymerization of 4‐methyl‐1,3‐pentadiene (MP) and copolymerization of 4‐methyl‐1,3‐pentadiene with alkenes (ethylene, 1‐pentene, 4‐methyl‐1‐pentene) were performed to investigate the effect of the so‐called backbiting coordination on the chemoselectivity of 1,3‐diene p

Structure and substituent effect on chir
Structure and substituent effect on chiral separation of some 4a-methyl-2,3,4,4a-tetrahydro-1H-fluorene derivatives and 4a-methyl-1,2,3,4,4a,9a-hexahydro-fluoren-9-one derivatives on CTA-I and chiralcel OJ chiral stationary phases
✍ Christian Roussel; Cristina Suteu; Latifa Shaimi; Mohammed Soufiaoui 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 129 KB 👁 3 views

The chromatographic parameters for 12 structurally related compounds in the 4a-methyl-2,3,4,4a-tetrahydro-1H-fluorene and 4a-methyl-1,2,3,4,4a,9a-hexahydrofluoren-9-one series are reported on CTA-I and Chiralcel OJ chiral stationary phases. Arrangement of the k' values according to configurationally

Conformationally locked heterocycles. St
Conformationally locked heterocycles. Structure of a doubly bridged pyrimido[1,2-a]pyrimidine from the hantzsch synthesis with 4-(2-hydroxyphenyl)but-3-en-2-one
✍ Jan Světlík; Tibor Liptaj; FrantiŠEk Tureček 📂 Article 📅 1999 🏛 Journal of Heterocyclic Chemistry 🌐 English ⚖ 406 KB

## Abstract 1D and 2D nmr spectroscopy was used to assign the structure to the minor product from cyclocondensation of 4‐(2‐hydroxyphenyl)but‐3‐en‐2‐one with cyanamide, which was identified as (6__R__\*, 9__R\*__, 15__R__\*, 17__R__\*)‐6,9‐dimethyl‐6,17:9,15‐dimemano‐6__H__,15__H__,17__H__‐[1,3,5]b