Design and Synthesis of Chiral Heteroleptic Rhodium(II) Carboxylate Catalysts: Experimental Investigation of Halogen Bond Rigidification Effects in Asymmetric Cyclopropanation

The design and synthesis of mechanically responsive materials is interesting because they are potential candidates to convert thermal energy into mechanical work. Reported in this paper are thermosalient effects in a series of halogen derivatives of salinazids. The chloro derivative, with higher electronegativity and a weaker inter-halogen bond strength (Cl...Cl) exhibits an excellent thermal response, whereas the response is weaker in the iodo derivative with stronger I...I halogen bonding. 3,5-Dichlorosalinazid (Compound-A) exists in three polymorphic forms, two room-temperature polymorphs (Forms I and II) and one high-temperature modification (Form III). The transformation of Form I to Form III upon heating at 328–333 K is a reversible thermosalient transition, whereas the transformation of Form II to Form III is irreversible and non-thermosalient. 3,5-Dibromo- (Compound-B) and 3-bromo-5-chloro- (Compound-C) salinazid are both dimorphic: the Form I to Form II transition in Compound-B is irreversible, whereas Compound-C shows a reversible thermosalient effect (362–365 K). In the case of 3,5-diiodosalinazid (Compound-D) and 3,5-difluorosalinazid (Compound-E), no phase transitions or thermal effects were observed. The thermosalient behaviour of these halosalinazid molecular crystals is understood from the anisotropy in the cell parameters (an increase in theaaxis and a decrease in thebandcaxes upon heating) and the sudden release of accumulated strain during the phase transition. The di-halogen salinazid derivatives (chlorine to iodine) show a decrease in thermal effects with an increase in halogen-bond strength. Interestingly, Compound-B shows solid-state photochromism in its polymorphs along with the thermosalient effect, wherein Form I is cyan and Form II is light orange.

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Design and Synthesis of a Chiral Halogen-Bond Donor with a Sp3-Hybridized Carbon–Iodine Moiety in a Chiral Fluorobissulfonyl Scaffold

Molecules ◽

10.3390/molecules25194539 ◽

2020 ◽

Vol 25 (19) ◽

pp. 4539

Author(s):

Hiroto Uno ◽

Kohei Matsuzaki ◽

Motoo Shiro ◽

Norio Shibata

Keyword(s):

Halogen Bond ◽

Aldol Reaction ◽

Asymmetric Induction ◽

Nmr Titration ◽

Titration Experiment ◽

Mukaiyama Aldol Reaction ◽

Design And Synthesis ◽

Mukaiyama Aldol

The first example of a chiral halogen-bond donor with a sp3-hybridized carbon–iodine moiety in a fluorobissulfonyl scaffold is described. The binaphthyl backbone was designed as a chiral source and the chiral halogen-bond donor (R)-1 was synthesized from (R)-1,1′-binaphthol in 11 steps. An NMR titration experiment demonstrated that (R)-1 worked as a halogen-bond donor. The Mukaiyama aldol reaction and quinoline reduction were examined using (R)-1 as a catalyst to evaluate the asymmetric induction.

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Experimental investigation of halogen-bond hard–soft acid–base complementarity

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520617001809 ◽

2017 ◽

Vol 73 (2) ◽

pp. 203-209 ◽

Cited By ~ 9

Author(s):

Asia Marie S. Riel ◽

Morly J. Jessop ◽

Daniel A. Decato ◽

Casey J. Massena ◽

Vinicius R. Nascimento ◽

...

Keyword(s):

Experimental Investigation ◽

Halogen Bond ◽

Noncovalent Interaction ◽

Computational Studies ◽

Donor Atom ◽

Acid Base ◽

State Data ◽

Lewis Bases ◽

Soft Acid ◽

Solution Speciation

The halogen bond (XB) is a topical noncovalent interaction of rapidly increasing importance. The XB employs a `soft' donor atom in comparison to the `hard' proton of the hydrogen bond (HB). This difference has led to the hypothesis that XBs can form more favorable interactions with `soft' bases than HBs. While computational studies have supported this suggestion, solution and solid-state data are lacking. Here, XB soft–soft complementarity is investigated with a bidentate receptor that shows similar associations with neutral carbonyls and heavy chalcogen analogs. The solution speciation and XB soft–soft complementarity is supported by four crystal structures containing neutral and anionic soft Lewis bases.

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Prostatic Acid Phosphatase (PAP) Differentiated Ultracytochemically from Lysosomal Acid Phosphate in the Rat with a PAP/Specific Substrate, Phosphorylcholine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115870 ◽

1975 ◽

Vol 33 ◽

pp. 450-451

Author(s):

W. Allen Shannon ◽

José A. Serrano ◽

Hannah L. Wasserkrug ◽

Anna A. Serrano ◽

Arnold M. Seligman

Keyword(s):

Acid Phosphatase ◽

Phosphate Buffer ◽

Prostatic Carcinoma ◽

Prostatic Acid Phosphatase ◽

Chemotherapeutic Agents ◽

Specific Substrate ◽

Acid Phosphate ◽

Lysosomal Acid ◽

Design And Synthesis ◽

New Chemotherapeutic Agents

During the design and synthesis of new chemotherapeutic agents for prostatic carcinoma based on phosphorylated agents which might be enzyme-activated to cytotoxicity, phosphorylcholine, [(CH3)3+NCH2CH2OPO3Ca]Cl-, has been indicated to be a very specific substrate for prostatic acid phosphatase (PAP). This phenomenon has led to the development of specific histochemical and ultracytochemical methods for PAP using modifications of the Gomori lead method for acid phosphatase. Comparative histochemical results in prostate and kidney of the rat have been published earlier with phosphorylcholine (PC) and β-glycerophosphate (βGP). We now report the ultracytochemical results.Minced tissues were fixed in 3% glutaraldehyde-0.1 M phosphate buffered (pH 7.4) for 1.5 hr and rinsed overnight in several changes of 0.05 M phosphate buffer (pH 7.0) containing 7.5% sucrose. Tissues were incubated 30 min to 2 hr in Gomori acid phosphatase medium (2) containing 0.1 M substrate, either PC or βGP.

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Tailoring microstructures of materials through biomimetics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148332 ◽

1993 ◽

Vol 51 ◽

pp. 500-501

Author(s):

Mehmet Sarikaya ◽

Ilhan A. Aksay

Keyword(s):

Chemical Properties ◽

Design And Synthesis ◽

Structure Sensitive ◽

Macro Scale ◽

Methods Of Synthesis ◽

Successive Level ◽

Engineering Materials ◽

Physical And Chemical ◽

And Chemical Properties ◽

Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

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Do moods and expectancies have unique or interactive effects?: An experimental investigation

PsycEXTRA Dataset ◽

10.1037/e514472015-591 ◽

2014 ◽

Author(s):

Shane Close ◽

Victoria Adkins ◽

Kandice Perry ◽

Katheryn Eckles ◽

Jill Brown ◽

...

Keyword(s):

Experimental Investigation ◽

Interactive Effects

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