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Chiral organosilanes do not exist in nature and are therefore absent from the "chiral pool". As a consequence, synthetic approaches toward enantiopure silanes, stereogenic at silicon, are rather limited. While catalytic asymmetric desymmetrization reactions of symmetric organosilicon compounds have been developed, the utilization of racemic silanes in a dynamic kinetic asymmetric transformation (DYKAT) or dynamic kinetic resolution (DKR) would significantly expand the breadth of accessible Si -stereogenic compounds. We now report a DYKAT of racemic allyl silanes enabled by strong and confined imidodiphosphorimidate (IDPi) catalysts, providing access to Si -stereogenic silyl ethers. The products of this reaction are easily converted into useful enantiopure monohydrosilanes. We propose a spectroscopically and experimentally supported mechanism involving the epimerization of a catalyst-bound intermediate.

The selective conversion of natural or synthetic neral to (1R,6S)-trans-isopiperitenol would enable and expedite sustainable routes to menthol 1,2 and cannabinoids 3-5 . However, this reaction has been considered impossible because its product is more reactive to the required acid catalysts than its starting material, resulting in several side products 6-9 . We now show that an unsymmetric, strong and confined chiral acid, a highly fluorinated imino-imidodiphosphate, catalyses this process with excellent efficiency and selectivity. Expanding the method to other α,β-unsaturated aldehydes could enable access to new cannabinoids and menthol derivatives not readily accessible previously. Mechanistic studies suggest that the confined catalyst accomplishes this reaction by binding the product in an unreactive conformation, thereby preventing its decomposition. We also show how (1R,6S)-trans-isopiperitenol can be readily converted to pharmaceutically useful cannabinoids and menthol, each in the shortest and most atom-economic routes so far., (© 2023. The Author(s).)

Background: There were described in veterinary literature, the possibility of pneumothorax as a complication of laparoscopic surgery in dogs undergoing laparoscopic ovariectomy associated with total laparoscopic gastropexy., Aim: To assess if spontaneous pneumothorax secondary to pneumoperitoneum is a real risk in dogs undergoing total laparoscopic gastropexy., Methods: Dogs undergoing totally laparoscopic gastropexy received chest X-rays (CXR) in lateral (left and right) and ventro-dorsal projection before and after the surgery. Two veterinary radiologists reported the x-rays and indicated the presence or not of pneumothorax., Results: Postoperative pneumothorax was not detected on postoperative CXR in the total of 76 dogs of the study., Conclusion: The odds risk of pneumothorax after total laparoscopic gastropexy surgical procedure is low., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Cryptorchidism is heritable in cats, and due to the pathological risk of testicular torsion, and the development of testicular neoplasia, cryptorchidectomy is the treatment of choice. For the intra-abdominal testes, a laparotomic approach is generally recommended; however, laparoscopic cryptorchidectomy in cats has been documented in a few clinical case reports. The aim of the study was to report the short-term clinical outcomes for 19 cryptorchid cats with intra-abdominal testes that underwent cryptorchidectomy with laparoscopic techniques. Medical records of client-owned sexually intact male cats that underwent laparoscopic cryptorchidectomy in different veterinary hospitals or ambulatory surgical services were reviewed. The procedure was performed in 19 cats. The average time (mean ± standard deviation, SD) for all procedures was 23 ± 6 min (range 15-35 min). The time for laparoscopic removal of a single abdominal testis was 22 ± 6 min, with 30 min for the bilateral abdominal testes. The time until hospital discharge varied depending on the surgeon's criteria, with a mean of 6 h (range 3-24 hrs). None of the cases analyzed showed any surgical complications. The results of this study suggest that laparoscopic cryptorchidectomy is an appropriate surgical procedure to treat cryptorchid cats with intra-abdominal testes, all with benefits of minimal invasion surgery.

(1) Background: The double pelvic osteotomy (DPO) is a prophylactic surgical procedure associated with 0.4% incidence of sciatic nerve injury. The piezoelectric cutting tool is a surgical device able to involve only mineralized tissue avoiding neurovascular tissue and other soft tissue. This study aimed to evaluate the sciatic nerve injury observed in dogs underwent iliac osteotomy performed using the piezoelectric cutting tool. (2) Methods: Dogs underwent DPO performed with piezoelectric cutting tool were included. Neurological assessment was performed 6 and 24 h after surgery and then repeated 12 days, 4 and 8 weeks after surgery. Temporary and or permanent sciatic nerve injury were recorded. (3) Results: 84 DPOs performed in fifty dogs were included. No temporary/permanent neurological disease associated with iatrogenic damage of the sciatic nerve were observed. (4) Conclusions: The iliac osteotomy performed with piezoelectric cutting tool was not associated to iatrogenic sciatic nerve injury.

Laparoscopic-assisted, laparoscopic, and endoscopic gastropexy techniques have been proven successful in recent years. Thanks to minimal invasiveness, low morbidity, and fast recovery, total laparoscopic gastropexy techniques have been gaining popularity. The objective of this study was to describe the use of a modified minimally invasive technique to perform prophylactic gastropexy in dogs. A case series study of 39 client-owned dogs was undertaken from June 2019 to August 2020. Each dog underwent total laparoscopic prophylactic gastropexy using a simple continuous barbed suture line and two laparoscopic needle holders without incising the seromuscular layer of the stomach and the abdominal wall. Surgical time, the number of stitches, and the length of suture were recorded. Telephone checks, owner questionnaires, and ultrasonographic exams were used to evaluate the effectiveness of the procedure after surgery. The median gastropexy surgical time was 12 min (range 4-30 min), and the median length of the suture line was 3 cm (range 2-4 cm). The last follow-up check was carried out 9 months (mean, range 3-14 months) after surgery, and all ultrasonographic exams (n = 29) showed an intact gastropexy. Intraoperative and postoperative complications were noted. This total laparoscopic gastropexy technique was found to be safe, fast, simple, and with a low morbidity rate. It appears to be a new alternative to other methods of prophylactic gastropexy; however, further research in this area is warranted.

Carbocations can be categorized into classical carbenium ions and non-classical carbonium ions. These intermediates are ubiquitous in reactions of both fundamental and practical relevance, finding application in the petroleum industry as well as the discovery of new drugs and materials. Conveying stereochemical information to carbocations is therefore of interest to a range of chemical fields. While previous studies targeted systems proceeding through classical ions, enantiocontrol over their non-classical counterparts has remained unprecedented. Here we show that strong and confined chiral acids catalyse enantioselective reactions via the non-classical 2-norbornyl cation. This reactive intermediate is generated from structurally different precursors by leveraging the reactivity of various functional groups to ultimately deliver the same enantioenriched product. Our work demonstrates that tailored catalysts can act as suitable hosts for simple, non-functionalized carbocations via a network of non-covalent interactions. We anticipate that the methods described herein will provide catalytic accessibility to valuable carbocation systems.

The trend in laparoscopy is to develop easy and rapid techniques associated with reduced intraoperative complications and decreased postoperative pain. The aim of this study was to compare combined laparoscopic ovariectomy (OIE) and laparoscopic-assisted incisional gastropexy (LAG) with combined laparoscopic OIE and total laparoscopic gastropexy (TLG) for surgical time, incidence of complications and postoperative pain. Twenty-eight female dogs were randomly assigned to the LAG group (n = 14) or the TLG group (n = 14). All laparoscopic procedures were performed using a three-port technique. The gastropexy was located 3 cm caudal to the 13th rib and 4 cm lateral to the rectus abdominis muscle. Surgical time (minutes [min]), intraoperative complications and postoperative complications were recorded. The Glasgow pain score (GPS) (short form) was calculated before surgery and at 1, 6, 12, 18 and 24 hr after extubation. Surgical time was significantly longer in the TLG group (48 ± 2 min) compared with the LAG group (39 ± 2 min). Minor postoperative complications occurred in both groups and included swelling (n = 2) and subcutaneous emphysema (n = 1). No significant differences regarding the GPS were recorded between groups. The GPS was significantly higher in both groups at 1 hr and 6 hr than before surgery. Two dogs in each group required rescue analgesia. Combined laparoscopic OIE and TLG require more time to perform than combined laparoscopic OIE and LAG. Neither procedure results in significant surgical complications. Postoperative pain for 24 hr was mild and comparable in both groups., (© 2020 The Authors. Veterinary Medicine and Science Published by John Wiley & Sons Ltd.)

High acidity and structural confinement are pivotal elements in asymmetric acid catalysis. The recently introduced imidodiphosphorimidate (IDPi) Brønsted acids have met with remarkable success in combining those features, acting as powerful Brønsted acid catalysts and "silylium" Lewis acid precatalysts in numerous thus far inaccessible transformations. Substrates as challenging to activate as simple olefins were readily transformed, ketones were employed as acceptors in aldolizations allowing sub-ppm level catalysis, whereas enolates of the smallest donor aldehyde, acetaldehyde, did not polymerize but selectively added a single time to a variety of acceptor aldehydes., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To compare meloxicam and robenacoxib for short-term postoperative pain management after combined laparoscopic ovariectomy and laparoscopic-assisted gastropexy., Study Design: Double-blind, prospective, randomised clinical trial., Animals: Twenty-six client-owned female dogs., Methods: Dogs undergoing combined laparoscopic ovariectomy and laparoscopic-assisted gastropexy were randomly divided into 2 groups. Before induction of anesthesia, 13 dogs received meloxicam (0.2 mg/kg subcutaneously), and 13 dogs received robenacoxib (2 mg/kg subcutaneously). Pain was scored with the Glasgow Composite Pain Scale (short form) before surgery and at 1, 6, 12, 18, and 24 hours after extubation. Rescue analgesia (tramadol, 3 mg/kg) was provided to dogs with a Glasgow pain score (GPS) ≥5. Glasgow pain scores were analyzed by ANOVA with treatment, age, and surgical time as fixed factors., Results: Glasgow pain scores were higher at 24 hours postsurgery in dogs treated with robenacoxib (2.18 ± 0.29) compared with those treated with meloxicam (0.68 ± 0.41, P = .04). Two dogs treated with meloxicam and 7 dogs treated with robenacoxib required rescue analgesia. Regardless of the treatment, the overall GPS was lower at 18 and 24 hours postsurgery when the surgical time was >40 minutes compared with surgical times ≤40 minutes, but surgical site inflammation was likely a confounding factor in this finding. Glasgow pain score was not affected by patient age., Conclusion: Meloxicam was more effective than robenacoxib at controlling pain in the population of dogs reported here., Clinical Significance: Preoperative administration of meloxicam effectively controls pain for 24 hours after combined laparoscopic ovariectomy and laparoscopic-assisted gastropexy, but rescue analgesia may be required., (© 2019 The American College of Veterinary Surgeons.)

Two dogs underwent a combined laparoscopic ovariectomy and total laparoscopic gastropexy. The intra-abdominal pressure and pulmonary compliance decreased, but the peak airway pressure increased at 20 min after the start of gastropexy with intracorporeal suturing. Right chest auscultation and percussion revealed reduced breath sounds and hyper-resonance. No abnormalities in the functioning of the instruments or diaphragmatic defects were detected. The tidal volume was reduced and a positive end-expiratory pressure of 5 cmH₂O was applied. The right chest of the two dogs was drained off: 950 mL (case 1) and 250 mL (case 2) of gas. After thoracentesis, the pulmonary compliance improved and surgery was completed successfully. The postoperative chest radiographs highlighted the residual right pneumothorax., Competing Interests: The authors declare no conflicts of interest., (© 2019 The Korean Society of Veterinary Science.)

Reactions that form a product with the same reactive functionality as that of one of the starting compounds frequently end in oligomerization. As a salient example, selective aldol coupling of the smallest, though arguably most useful, enolizable aldehyde, acetaldehyde, with just one partner substrate has proven to be extremely challenging. Here, we report a highly enantioselective Mukaiyama aldol reaction with the simple triethylsilyl (TES) and tert -butyldimethylsilyl (TBS) enolates of acetaldehyde and various aliphatic and aromatic acceptor aldehydes. The reaction is catalyzed by recently developed, strongly acidic imidodiphosphorimidates (IDPi), which, like enzymes, display a confined active site but, like small-molecule catalysts, have a broad substrate scope. The process is scalable, fast, efficient (0.5 to 1.5 mole % catalyst loading), and greatly simplifies access to highly valuable silylated acetaldehyde aldols., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

The enantioselective allylation of aldehydes to form homoallylic alcohols is one of the most frequently used carbon-carbon bond-forming reaction in chemical synthesis and, for several decades, has been a testing ground for new asymmetric methodology. However, a general and highly enantioselective catalytic addition of the inexpensive, nontoxic, air- and moisture-stable allyltrimethylsilane to aldehydes, the Hosomi-Sakurai reaction, has remained elusive. Reported herein is the design and synthesis of a highly acidic imidodiphosphorimidate motif (IDPi), which enables this transformation, thus converting various aldehydes with aromatic and aliphatic groups at catalyst loadings ranging from 0.05 to 2.0 mol % with excellent enantioselectivities. Our rationally constructed catalysts feature a highly tunable active site, and selectively process small substrates, thus promising utility in various other challenging chemical reactions., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Quaternary stereocenters are found in numerous bioactive molecules. The Tsuji-Trost reaction has proven to be a powerful C-C bond forming process, and, at least in principle, should be well suited to access quaternary stereocenters via the α-allylation of ketones. However, while indirect approaches are known, the direct, catalytic asymmetric α-allylation of branched ketones has been elusive until today. By combining "enol catalysis" with the use of CO2 as a formal catalyst for asymmetric catalysis, we have now developed a solution to this problem: we report a direct, highly enantioselective and highly atom-economic Tsuji-Trost allylation of branched ketones with allylic alcohol. Our reaction delivers products bearing quaternary stereocenters with high enantioselectivity and water as the sole by-product. We expect our methodology to be of utility in asymmetric catalysis and inspire the design of other highly atom-economic transformations., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The benzimidazole core is a common moiety in a large number of natural products and pharmacologically active small molecules. The synthesis of novel benzimidazole derivatives remains a main focus in medicinal research. In continuation of the efforts towards Ce(III) catalysts for organic transformations, we observed for the first time the activity of the iodide ion and copper cation in activating CeCl3·7H2O in the selective formation of prototypical 2-substituted benzimidazoles. The one-pot CeCl3·7H2O-CuI catalytic system procedure includes the cyclo-dehydrogenation of aniline Schiff's bases, generated in situ from the condensation of 1,2-phenylenediamine and aldehydes, followed by the oxidation with iodine, which works as a hydrogen sponge. Mild reaction conditions, good to excellent yields, and clean reactions make the procedure a useful contribution to the synthesis of biologically active fused heterocycles containing benzimidazoquinazolines.

Reported here are procedures for a one-pot oxidation and rearrangement of propargylamines to synthesize enaminones, with supporting mechanistic studies. Also reported are the extended one-pot syntheses of pyrazoles, including celecoxib and various heterocyclic compounds.

Cerium(III) salts have recently gained increasing attention in the synthetic community, owing to the powerful features that are reviewed in detail in this tutorial. This review reports significant examples of cerium(III) promoted synthesis of heterocyclic structures, initially dealing with the synthesis of five- and six-membered ring nitrogen containing heterocycles, then describing the preparation of their oxygenated analogues and finally discussing the achievement of seven-membered rings and mixed heterocyclic motifs.

A case of a feline Merkel cell tumour is described. An 8-year-old, female cat developed a round, alopecic, reddish mass on the nose. Wide excisional surgery was performed with cartilage resection. Histologically the mass was composed of solid islands of mostly basophilic densely packed cells with a scant cytoplasm, which was suggestive of a neuroendocrine origin. Results of immunohistochemical studies using antibodies against neurone-specific enolase, chromogranin, synaptophysin and pan-cytokeratin allowed classification of the lesion as a Merkel cell tumour. Ultrastructurally, dense core granules were identified in the cytoplasm. In a 2-year follow-up no relapses or metastases were observed. The clinical course recorded is in contrast with the malignant nature of a Merkel cell tumour recently described in a cat and of the human Merkel cell tumour, but is similar to the course of the canine Merkel cell tumour which is often benign. Early diagnosis along with the use of wide surgical excision might be considered an important factor in preventing relapse of this tumour.