1,2:5,6-Di-O-isopropylidene-α-d-3-glucofuranosyl (R p)-2-(diphenylphosphino)ferrocene-1-carboxylate

The title compound, [Fe(C5H5)(C30H32O7P)], which is an intermediate in the synthesis of (R p)-2-(diphenylphosphino)ferrocene-1-carboxylic acid, crystallizes in the common chiral space group P212121. In general, the molecular geometry is very similar to that of the corresponding 2,1′-bis(diphenylphosphino) congener. The ferrocene unit assumes a regular geometry with the proximal bulky substituents efficiently avoiding mutual spatial contacts. In the crystal, the molecules participate in weak intra- and intermolecular C—H⋯O interactions.

The title compound, [Fe(C 5 H 5 )(C 30 H 32 O 7 P)], which is an intermediate in the synthesis of (R p )-2-(diphenylphosphino)ferrocene-1-carboxylic acid, crystallizes in the common chiral space group P2 1 2 1 2 1 . In general, the molecular geometry is very similar to that of the corresponding 2,1 0 -bis(diphenylphosphino) congener. The ferrocene unit assumes a regular geometry with the proximal bulky substituents efficiently avoiding mutual spatial contacts. In the crystal, the molecules participate in weak intra-and intermolecular C-HÁ Á ÁO interactions.
In the solid state, the individual molecules are involved in intra-and intermolecular C-H···O contacts (Table 1).

S3. Refinement
All H-atoms were included in their calculated positions and refined as riding atoms. The unusually high 'positive′ residual electron density can be attributed to lone electron pair at phosphorus (N.B.: The second largest residual electron density peak has only 0.63 e Å -3 ). Attempted refinement of this largest maximum as a helium atom (two electrons) resulted not only in reasonable geometry (P-X = 1.354 (5) Å; C-P-X angles = 103.5 (2)-124.6 (2) °) but also in a significant decrease in the R-indices (R = 0.0314, wR = 0.0395% for observed diffractions) and extremes on the residual electron denisty map (0.39, -0.33 e Å -3 ). Besides, the dummy atom is found in a position suitable for the formation of an intramolecular C-H···X contact with H35 (cf. C35···X = 2.14 Å, C35-H35···X = 178 °)

Figure 1
A view of the molecular structure showing the atom numbering scheme and displacement ellipsoids for the non-H atoms at the 30% probability level.

Data collection
Nonius KappaCCD diffractometer Radiation source: fine-focus sealed tube Horizontally mounted graphite crystal monochromator Detector resolution: 9.091 pixels mm -1 ω and π scans to fill the Ewald sphere 68616 measured reflections 7369 independent reflections 6632 reflections with I > 2σ(I)  (4)