Crystal structure of 1,3-di-tert-butyl-2-chloro-1,3,2-di-aza-phospho-rinane - a saturated six-membered phospho-rus nitro-gen heterocycle with a partially flattened chair conformation and a long PIII-Cl bond.

ABSTRACT: Colourless blocks of 1,3-di-tert-butyl-2-chloro-1,3,2-di-aza-phospho-rinane, C11H24ClN2P (1), were obtained by sublimation in vacuo slightly above room temperature. The asymmetric unit of the monoclinic crystal structure of the six-membered N-heterocyclic compound is defined by one mol-ecule in a general position. The six-membered ring of the mol-ecule adopts a cyclo-hexane-like chair conformation; the chair at one side is to some extent flattened as a result of the approximately trigonal-planar coordination of both nitro-gen atoms. In detail, this modified chair conformation is characterized by an angle of 53.07?(15)° between the plane defined by the three carbon atoms and the best plane of the two nitro-gen atoms and the two carbon atoms bound to them, and an angle of 27.96?(7)° between the latter plane and the plane defined by the nitro-gen and phospho-rus atoms. The tert-butyl groups are oriented equatorially and the chloro substituent is oriented axially. The P-Cl bond length of 2.2869?(6)?Å is substanti-ally longer than the P-Cl single-bond length in PCl3 [2.034?Å; Galy & Enjalbert (1982 ?). J. Solid State Chem. 44, 1-23]. Inspection of the inter-molecular distances gives no evidence for inter-actions stronger than van der Waals forces. The closest contact is between the Cl atom and a methyl-ene group of a neighbouring mol-ecule with a Cl?C distance of 3.7134?(18)?Å, excluding a significant influence on the P-Cl bonding.

SUBMITTER: Mecke E 

PROVIDER: S-EPMC6505585 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature