𝔖 Bobbio Scriptorium
✦   LIBER   ✦

N2-Elimination from a [3 + 2]-Cycloadduct of Diazoalkane and Amino(methylene)phosphane to give a λ3-Phosphirane

✍ Scribed by Prof. Dr. Edgar Niecke; Priv.-Doz. Dr. Wolfgang W. Schoeller; Dipl.-Chem. Dirk-Andreas Wildbredt


Book ID
101551928
Publisher
John Wiley and Sons
Year
1981
Tongue
English
Weight
228 KB
Volume
20
Category
Article
ISSN
0044-8249

No coin nor oath required. For personal study only.

✦ Synopsis


These distances indicate considerable mesomeric interaction of the free electron pair on C52 with the )C=O groups, with the free electron pair on the imide nitrogen, and with the phosphorus atoms. The cyclopentadiene ring in (5) is pentahapto bonded to molybdenum. The bond lengths in the M O ( C O ) ~( C ~H ~) part of the molecule are normal (in pm): Mo-CP = 230-236 CP-CP = 139-142 Mo-ClO = 199(1) Mo-C20 = 196(1) CIO-OCI = 114(1) CZO-OC2 = 115(1)

A further proof for the constitution of (5) is its smooth oxidation to (4) [eq. (b)]:

(5) + Iz + (4) + HI

Procedure (b)

A solution of [MO(C,H,)(CO>,]~ (1.2 g, 2.45 mmol) and (PP) (2.36 g, 4.91 mmol) in boiling toluene is stirred until evolution of CO is complete. Brown (3) crystallizes from the dark-brown solution; yield 95%.-The iodide (4) is prepared by oxidation of (3) (2.38 g, 3.41 mmol) with iodine (0.435 g, 3.42 mmol) in ether/l,2-dichloroethane (1 : 1) at "C; dark-red crystals, yield 80%.-When (3) is heated for several days at 80°C in toluene, (5) is obtained as large, yellow crystals; yield 40-60%.